PHYSICS FORM FOUR REGIONAL EXAMS (MOCK, PRE-NATIONAL, etc.)

TANZANIA HEADS OF ISLAMIC SCHOOLS COUNCIL

FORM FOUR INTER ISLAMIC MOCK EXAMINATION

031/1 PHYSICS 1

(For Both School and Private Candidates)

Time: 3 Hours Tuesday, 13th September 2022 a.m.

Instructions

1. This paper consists of sections A, B and C with a total of eleven (11) questions.

2. Answer all questions in sections A and B and any two (2) questions from section C.

3. Section A carries fifteen (15) marks, section B carries sixty (60) marks and section C carries twenty-five (25) marks.

4. Cellular phones and any unauthorized materials are not allowed in the examination room.

5. Non-programmable calculators may be used.

7. Where necessary the following constants may be used.

1. Acceleration due to gravity, g = 10m/s2.
2. Pie, π= 3.14
3. Density of water ∫=1000kg/m3
4. Speed of light waves = 3.0 x 108m/s.
5. Velocity of sound in air, V = 340m/s.
6. Specific heat capacity of water = 4200J/kgoC.
7. Specific heat capacity of copper calorimeter = 390J/kgoC.
8. Density of gold = 19.3g/cm3 and density of silver = 10.5g/cm3.
9. Relative density of alcohol = 0.8
10. Resistivity of copper wire = 1.68 x 10-8Ωm.

SECTION A (15 Marks)

Answer all questions in this section

1. For each of the items (i) to (x) choose and write the letter of the most correct answer in the answer booklet (s) provided.

(i) A teacher of Physics was doing a practical and she found that the reading of a burette to be 13.90cm3, 60 drawing pins each of average volume of 0.1cm3 were added to the water, the new reading now is:

1. 13.96 cm3
2. 19.70 cm3
3. 19.69 cm3
4. 19.90 cm3
5. 73.90 cm3.

(ii) Ten best students from Murubona International School were taken to China and they visited one of the lakes there and they found that pond skaters were walking on the surface of that lake. This is because of the:

1. Surface tension of that water
2. Upthrust of the water
3. Density of that water
4. Capillarity of that water
5. Force of that water.

(iii) A crate of soda with mass 50kg will just begin to slide with constant speed down a rough ramp (slope) at 30o to the horizontal. The coefficient of friction which is static was:

1.  0.6774
2. 0.5774
3. 200.0000
4. 346.4000
5. 0.5000.

(iv) It has been proved by scientists that as one goes far away from the earth’s surface, the density of air will:

1. Decrease
2. Increase
3. Remain constant
4. Become greater than its weight
5. Be zero.

(v) Which amongst the following could be the best reason as to why the sky is believed to appear blue while being observed from the earth’s surface?

1. Selective scattering of sunlight
2. Regular reflection of sunlight
3. Irregular reflection of sunlight
4. Diffuse refraction of sunlight
5. Selective scattering of moon light.

(vi) A measuring cylinder is filled with oil. A girl says that the pressure at the bottom of the cylinder depends on:

1. The height of the oil

2. The area at the bottom

3. The oil lubrication property

4. The oil density

Which of A, B, C, D, and E is correct?

1. 1 and 3
2. 2 and 4
3. 1 and 2
4. 1 and 4
5. 3 and 4.

(vii) A rectangular wooden block of density 0.8g/cm3 has dimensions 0.5m x 0.8m x 6m what maximum pressure will it exert on the ground?

1. 48,000N/m2
2. 4000N/m2
3. 2.4N/m2
4. 19,200N/m2
5. 400N/m2.

(viii) One of Art’s students was found stretching a certain wire and that wire stayed inelastic. Explain as a physics student whether the force applied is:

1. Zero
2. Independent of extension
3. Directly proportional to extension
4. Inversely proportional to extension
5. Dependent and independent of extension.

(ix) Normally it is seen practically that an airship is always floating high above the ground, it means in this case:

1. The air upthrust is equal to airship weight
2. The air temperature inside the airship is equal to the air temperature outside
3. The air density outside the airship is equal to the air density inside
4. The air temperature inside the airship is less than air temperature inside the airship
5. The air temperature is always not varying.

(x) A nail is being pulled by Amina, a form three student at Yombo Secondary using a string from a wall. The string forms an angle of 30o with the nail. If the force being used is 10N, what magnitude of the force tends to bend the nail?

1. 8.66N
2. 0.866N
3. 5N
4. 0.500N
5. 50N.

2. Match the descriptions of the uses of electromagnetic radiations in LIST A with the correct names of the waves in LIST B by writing a letter in the answer sheet provided.

 LIST A LIST B (i) Electromagnetic radiation which are used to increase the rate of growth of chickens. (ii) Electromagnetic radiation which are used by the global positioning satellite (GPS) to precisely pin point the location of the targets. (iii) Electromagnetic radiations which are used for satellite communications. (iv) Electromagnetic radiations which are used in CD and DVD players to read the content of the disk (v) Electromagnetic radiations which are used in remote sensing of vegetation and for identification of different objects. Radio waves Micro waves Infra-red Visible light Ultra-violet X-rays Gamma rays

SECTION B (60 Marks)

Answer all questions in this section

3. (a) The Russia – Ukraine war has a tension of use of weapons of mass destruction. Mention three possible dangers associated with these weapons.  [06 marks]

(b) A mirage is often seen by a motorist as a pool of water on the road some distance ahead. With the aid of diagram, give an explanation of its formation.  [04 marks]

4. (a) Measurement is an essential tool in day to day life, briefly explain how measurement can assist the human being in the following areas:

(i) In architecture

(ii) In hospital [05 marks]

(b) A crown made of gold and silver has a volume of 60cm3 and mass of 1.05kg. Estimate the exact mass of gold contained in the crown. [05 marks]

5. (a) Amongst advantages of the diode is that, it is a suitable device for converting sinusoidal wave form into unidirectional wave form of electricity. Explain how is this done in real

life situation. [05 marks]

(b) Transistors are sincerely base elements of modern electronics and all the people have great interest with them. Suggest utmost five applications that transistors have to people.

[05 marks]

6. (a) How is the principal focus of a convex mirror explained as far as light is concerned,

A concave mirror is used to form an image of an object pin where the object must be placed to obtain:

(i) An upright, enlarged image

(ii) An image the same size as the object. [05 marks]

(b) A diagram below shows the path of a ray of light through one corner of a cube ice. Find:

(i) The angle of incidence as the AB

(ii) The angle of refraction at this face. [05 marks] 7. (a) It is believed by physicists here in Tanzania and the whole world that we cannot verify ohm’s law by using a filament lamp. Explain why is this true? [3 marks]

(b) As a form four physics student do you think that electromotive force (e.m.f) is different from potential difference (V). Give three points (if any). [3 marks]

(c) What is the resistance of copper wire of length 20cm and diameter 0.080cm? [4 marks]

8. (a) Explain with one reason as why Tanzania ports in Dar es Salaam and Zanzibar block and tackle pulleys are commonly used. [2 marks]

(b) Exactly explain to why the efficiency of a pulley system is always less than 100%. Give only two reasons. [2 marks]

(c) A wheel and axle with an efficiency of 90% is to be used to raise load of 10,000N. The radius of the wheel is 40cm while that of axle is 5cm, calculate:

(i) The velocity ratio of the wheel and axle [2 marks]

(ii) The mechanical advantage of the wheel and axle [2 marks] (iii) The effort required to raise the 10,000N load [2 marks]

SECTION C (25 Marks)

Answer only two (2) questions in this section

9. (a) Vectors are totally different from scalars in all aspects including direction. What do you think are two conditions to be satisfied for two vectors to be equal? [4 marks]

(b) State and explain practically the meaning of triangle law of vector addition. [2 ½ marks]

(c) Two vectors, one of 8N and the other 6N, are acting on a body. Given that the two forces are acting perpendicularly to each other. Find the magnitude of the third force which would just counter balance the two forces. [6 marks]

10. (a) Students of form four in Uganda were not taught about electronics. Suppose you were invited to speak to them, using a labelled diagram explain how full-wave rectification can be achieved by using two diodes and centre-tapped transformer. [6 marks]

(b) (i) Electrical energy is distributed in all parts of Tanzania by the National Grid

System which transmits a.c at very high voltage. Why is an a.c and not a d.c used? [2 marks]

(ii) Six cells each having an emf of 2V and internal resistance of negligible resistance, a 1.4Ω resistor and a metal-filament lamp. The ammeter reads 3A, what readings would you expect from a high resistance voltammeter connected across the battery terminals? [4 ½ marks]

11. (a) Discuss the meaning of the term “Laws of Stars”. [2 ½ marks]

(b) “Astronomy has a vital Role over thousands of years”. Elaborate four (4) ways to support that statement. [4 marks]

(c) What do you think are the three basic characteristics of planet until to date? [3 marks]

(d) What do you understand by the term constellation as far as astronomy is concerned and hence explain three of its uses in day to day life situations. [3 marks]

LEARNINGHUBTZ.CO.TZFORM FOUR PHYSICS REGIONAL SERIES-87 YEAR-2022

PRESIDENT'S OFFICE REGIONAL ADMINISTRATION AND LOCAL GOVERNMENT
KILIMANJARO REGIONAL COMMISSIONER'S OFFICE
FORM FOUR MOCK EXAMINATION

PHYSICS 1

CODE:31/1

TIME: 3 HOURS 01/07/2022

INSTRUCTIONS

1. This paper consists of section A, B and C with total of eleven (11) questions.
2. Answer all questions in section A and B and two (2) questions from section C.
3. Section A carries fifteen (15) marks, section B sixty (60) marks and section c carries twenty five (25) marks.
4. Cellular phones and any unauthorized materials are not allowed in the examination room.
5. Non-programmable calculators and mathematical tables may be used.
7. Where necessary the following constants may be used:
1. Acceleration due to gravity, g = 10 m s-2.
1. Density of water, p = 1000 kg m-3 or 1 gcM-3.
2. Pie, 7r. = 3.14.
3. Specific latent heat of vaporization of water = 2.3 x 106 J / Kg

SECTION A (15 Marks)
Answer all questions in this section,

1. For each of the item (i) - (x), choose the most correct answer from 'among the given alternatives and write its letter beside the item number hi the answer booklet provided.

i. Which of the following matches is not correct in terms-of its SI UNIT?

1. Mass — Kilogram
2. Force Newton
3. Length — Meter
4. Time — Minutes
5. Amount of substance - Mole

ii. A stone of mass 18g was immersed into a liquid and then removed. Figure 1 below shows initial liquid level, A, when the stone was fully immersed and the final level, B after the stone has been removed. Find the density of the stone. Figure 1
1. 2.25 g/cm3
2. 1.80 g/cm3
3. 2.00 g/cm3
4. 9.00 g/cm3
5. 12.00 g/cm3

iii. In a simple electric motor the commutator

1. Connects the brushes together
2. Reverses the magnet field
3. Charges the current strength in the coil
4. Changes the current direction in the coil.
5. Reverse the battery poles.

iv. Kelvin scale has;

1. One fixed point
2. Two fixed points
3. Three fixed points
4. One fixed and two variable points
5. None of the above

v. The resultant of two forces of 3N and 4N acting at right angle is equal to;

1. 4N
2. 3.5N
3. 7,0N
4. 3N
5. 5N

vi. The cost of electricity for a 2000W electric fire used for 10;3.0 hours at the rate of Tshs 8 per KWh is;

1. Tshs 168
2. Tshs 80
3. Tshs 64.8
4. Tshs 1,680
5. Tshs 8,000

vii. Oil is used as a lubricant in a machine because it has

1. Low density
2. High viscosity
3. Low pressure
4. High pressure
5. Low viscosity

viii. A bar of copper is heated from 293K to 333K. Identify the false statement among the following

1. Its density will increase slightly
2. Its length will increase slightly
3. Its electrical conduction will decrease slightly
4. Its mass will not change
5. Its weight will remain unchanged

ix. The graph below shows the decay curve of a radioactive substance. What is the half-life? Figure 2
1. 1 minute
2. 2 minutes
3. 3 minutes
4. 4 minutes
5. 5 minutes

x. The frequency of a wave increases when the speed remains the same. What happen to the distance between two consecutive crests?

1. It increases
2. It decreases
3. Stay unchanged
4. It increases and then decreases
5. It decreases first and then increases

2. Match the items from List A with the corresponding labeled parts of the a.c generator in List B by writing the letter of the correct response beside the item number in the answer booklet provided.

 LIST A LIST B (i) Are used to provide a constant magnetic field. (ii) As it rotates, the magnetic field through it changes, which induces an e.m.f. (iii) External circuit. (iv) They turn with the coil. They are made of a good conductor such as copper. (v) They keep electrical contact with the slip rings but do not move to the external circuit. SECTION B (60 Marks)

Answer ALL questions in this section

3. (a) Figure 4 below shows rays of light AO, BO, CO incident on a glass --air interface. OA OP and OC are the corresponding emergent rays. Study and answer the questions that follow: Figure 4

Determine the critical angle and refractive index of the glass material (06 marks)

(b) One of the common method used in our family to preserve Irish potatoes, is to put them in water.
Explain briefly how this method preserve and keep potatoes health than when it is not used. (04 marks)

4. (a) A claw hammer can work as first class and third class lever. Justify this statement. (01 mark)

(b) (i) Differentiate sound waves from electromagnetic waves. (04 marks)

(ii) Figure 5 below is a wave of string vibrating with a frequency of 500HZ. Determine 1) Amplitude 2) Wavelength 3) Speed of the wave Figure 05

5. (a) Briefly explain the following phenomenon;

1. A cool breeze blows from the sea on a hot summer day.
2. Condensation of water vapour on a bath room mirror warms the bathroom

(b) A uniform half meter rule AB is freely pivoted at 10cm from end A and balance when a body of mass 35g is hanged at 2cm from end A.

1. Sketch the diagram to illustrate the information above
2. Calculate the mass of the ruler

6. (a) Using domain theory, explain the process of magnetization.

(b) The kettle contains 1.6kg of water, is left switched on, after starting to boil;

1. How much heat energy will be used in turning all the water to steam.
2. How long will it take for the 2.5kw kettle to boil dry. (06 marks)

7. (a) Give the most suitable type of electromagnetic radiation for the applications stated below.

1. Satellite communications.
2. Disinfecting water.
3. Thermal imaging.
4. Sterilizing food.
5. Vision. (05 marks)

(b) A particular radioactive has a half— life of 2.0 hours. A sample gives a count rate of 2400 counts per second at 11:00 am. When will the count have dropped to approximately 300 counts per second in the same counting system? (05 marks)

8. (a) In the set up shown in figure 6 below a light copper ring is supported above the solenoid with a wooden peg. Explain why the copper ring becomes hot when the switch is closed. Figure 06

(b) Briefly explain

1. Meteorites
2. Four (4) effects of global warming (04 marks)

SECTION C (25 Marks)
Answer two (2) questions from this section.

9. (a) Give three reasons, why Tanzania decided to shift from analogue to digital signal transmission?

(b) In only one of the given diagrams in figure 7 below, identify the circuits in which the lamp lights by giving a reason.(02 Marks) Circuit A Circuit B Figure B

(c) The air in each of the four tyres of a motor car exerts a pressure above atmospheric pressure of 3 x 105 N/m2If each tyre is in contact with the ground over an area Of 80cm.2. Estimate the mass of the car. (05 marks)

10. (a) Wind energy is one of the sustainable energy sources with relative lOw running costs. Describe how electric energy is harnessed from wind energy. (05 marks)

1. In a X- ray tube, explain why the filament is made of tungsten metal? (2.5 marks)
2. (i) State the factors on which the strength of a transformer depends (02 marks)

(ii) A transformer steps down from 240V to 6V. If there are 1600tums on the primary, how many turns are needed on the secondary? If the transformer has an efficiency of 85% what current is taken from the 240V supply when 2A are taken from the secondary?

11. (a) The form three students at a certain secondary school perform an experiment to determine unknown resistance-of the wire X by using a meter bridge circuit. The apparatus arrangement used is as shown in the figure 8 below, where AB is a constant wire of length one meter. Find the resistance of wire X. Figure 08

(b) The house is fitted and uses the following electrical appliances with their respective power rating as shown in the table below

 AN ELECTRIC APPLIANCE POWER RATING 4 bulbs 100 W each Heater 1,200W . Electric iron 1,000W Television 400W

If each electrical appliance is used for 4 hours every day and the cost of using it is Shs 3501= per unit, find the cost of operating these items for 10 days. (5.5 marks)

LEARNINGHUBTZ.CO.TZFORM FOUR PHYSICS REGIONAL SERIES-38 YEAR-2022

PRESIDENT’S OFFICE REGIONAL ADMNINSTRATION AND LOCAL GOVERNMENT

LUDEWA DISTRICT COUNCIL

FORM FOUR MOCK EXAMINATION JUNE, 2022

031/1 PHYSICS 1

TIME: 3HRS Friday Morning, June 10th, 2022 a.m.

INSTRUCTIONS

1. This paper consists of sections A, B and C with a total of eleven (11) questions.

2. Answer all questions in sections A and B and only two (2) questions from section C.

4. Non-programmable calculators and four figures may be used.

5. Cellular phones are not allowed in the examination room.

6. Where necessary the following constants may be used;

(i) Acceleration due to gravity, g = 10m/s2 or 10N/kg

(ii) Density of water = 1g/cm3

(iii) Specific latent heat of condensation of steam (Lw) = 2.26 × 106 J/kg

(iv) Specific heat capacity of water (Cw) = 4200J/kgk

(v) Specific heat capacity of copper = 390J/kgk

(vi) Velocity of sound in air = 330 m/s

(vii) Standard atmospheric pressure = 101300 N/m2

SECTINS A (15 Marks)

1.For each of the items (i) – (x), choose the correct answer from among the given alternatives and write its letter beside the item number in the answer sheet provided.

(i). The International system of units, SI has decided to use the wavelength of monochromatic light (wavelength of orange-red light emitted by the isotope krypton-86) as the standard of length.

What among the following is not true about the information above?

1.  The wavelength of light is not affected by change in place
2.  The wavelength of light is not affected by time
3. The wavelength of light is not affected by temperature
4. That kind of light is easily reproducible in any good laboratory.
5. The wavelength of light is constant at standard temperature and pressure.

(ii) Any phenomenon which repeats itself at regular interval, can be used as a measure of time. Which among the following phenomena is not likely to be?

1.  Oscillation of pendulum
2. Revolution of the earth around the sun
3.  Rotation of earth about its axis
4. Revolution of the moon around the earth
5. Rotation of wheels of a very fast-moving sports car.

(iii). A car moving with a velocity of 40km/h can be stopped by applying brakes in 2m. If the same car is moving with the speed of 80km/h, what is the minimum stopping distance?

1.  16 m
2. 12 m
3. 8 m
4. 4 m
5. 2 m

(iv) A clinical thermometer is used to measure the temperature of human bodies. During its construction, the biomedical equipment engineers prefer to use mercury as a thermometric liquid than water or alcohol. What do you think is the reason behind?

1.  It is expensive
2. It is opaque and does not need coloring
3.  It is more sensitive to temperature
4. It has high specific high heat capacity
5. It is the most conducting and less dense than all other liquids.

(v) Figure 1 below shows a block being pulled along a track. If a force of 20N is applied in the direction A at an angle of 60º, what is the value of the force which tend to move the block in the direction of B? Figure 1
1.  17N
2. 12N
3.  20N
4. 10
5. 21N

(vi) A measuring cylinder is filled with oil. A girl says that the pressure at bottom of the cylinder depends on:

1. The height of the oil

2. The area at the bottom

3. The oil lubricating property

4. The oil density

Which of the following alternatives is not correct?

1.  1 and 3
2. 2 and 4
3. 1 and 2
4. 1 and 4
5. 3 and 4

(vii) The monkey is descending from the branch of a tree with a constant acceleration. If the breaking strength of the branch is 75% of the weight of the monkey, what will be the minimum acceleration with which the monkey can slide down without breaking the branch?

1.  g
2. 3g
3.  g⁄2
4. g⁄4
5. 4g

(viii) Illuminated smoke particles, suspended in air, are viewed with a microscope and are seen to vibrate continuously. What do you think this vibration of the smoke particles is caused by?

1.  They are bombarded continuously by air molecules
2.  Agitated by sound waves from the surrounding room
3.  Shaken by the vibration of the molecules within them
4.  They are supplied with energy by the light illuminating them.
5. Moved around by convection currents

(ix) If no lubricating oil is used, the metal X of a piston rubs against metal Y of an engine casing. The amount of heat produced depends on:

1.  Specific heat capacity of X
2. Frictional force between X and Y
3.  The specific heat capacity of Y
4. The conductivity of X and Y
5. The mass of Y.

(x) The table below shows the saturation vapour pressure (S.V.P) of a liquid in centimetres of mercury.

 Temp (℃) 20 30 40 50 60 70 80 S.V. P 30 44 52 68 74 78 84

At standard (normal) atmospheric pressure, the boiling point of the liquid is about:

1.  35℃
2. 40℃
3. 55℃
4. 65℃
5. 80℃

2. Match the parts of a certain optical instrument from LIST A with the corresponding functions in LIST B by writing the letter of the correct response beside the item number in answer sheet provided.

 LIST A LIST B Figure 2 Magnifies and invert image so as to be seen upright on the screen. It inverts image side way Real image It diverges light to focus the image on the screen Virtual image It concentrates light which would otherwise be partly wasted. It is a doublet to reduce chromatic aberration Provides illumination It directs maximum amount of light from the image to the slide

SECTION B (60Marks)

3. (a) You are with density bottle, water, oil and beam/ digital balance. Explain briefly the procedures you could use to determine the relative density of oil and deduce its formula. (6 marks)

(b) A relative density bottle has a mass of 14.6g when dry and empty. Its mass is 58.1g when full of turpentine and 64.6g when full of water. Find the relative density (R.D) of turpentine. (4 marks)

4. (a) Repulsion is a sure test for electrification. As a form four student how can you explain this phenomenon? (5 marks)

(b) Although ordinary rubber is an insulator, the rubber tyres of an air craft are made slightly conducting. Explain why. (5 marks)

5. (a) “The specific heat latent heat of vaporisation of water is 2.26 × 106 J/kg”. The statement confused some students at a certain school. Assist them by giving the meaning of the statement. (3 marks)

(b) 100g of dry steam at 100℃ is mixed with 2kg of water at 20℃. Determine the final temperature of the steam when all the steam has condensed. (7 marks)

6. (a) You are provided with two types of mirrors, concave mirror and convex mirror. What type of the mirror among the two will you prefer or driving a car to see the traffic at your back? Explain your choice. (4 marks)

(b) A far-sighted woman has a near point of 1.5m. Calculate the focal length of the lens for her ` eyeglasses so that she can read a book held at 25cm. Also find power of the lens.  (6 marks)

7. (a) A drum at station A is connected to a wire string at station B. A man at A beats the drum while another person at B places his ear at the wire and hears two sounds separated by the time interval of 0.5 seconds. If the velocity of sound in the wire string is 5280m/s. How far apart are the two men. (5 marks)

(b) How long will it take a 240V, 3000W electric immersion heater to raise the temperature of 150 litres of water in a well lagged copper tank of mass 20kg from 15℃ to 70℃. Also find the cost at 5 shillings per kwh. (5 marks)

8. (a) Mr. Jacob said that “Stars and planets are all the same since they are all found in the space (sky)”. Argue for or against the statement by giving six (6) points to support your answer. (6 marks)

(b) The greenhouse effect is the process in which the emission of radiation by the atmosphere warms the earth’s surface. This effect is useful to all life on the earth’s surface, especially in maintaining the moderate temperature on the earth. There are some gases which are associated with this effect, and if these gases are present in high amount, they disturb temperature on the earth’s surface. Explain briefly four of these gases. (4 marks)

SECTION C (25 Marks)

9. (a) Imagine that the room in which you are seated is filled with a uniform magnetic field pointing vertically downward. At the entre of the room, an electron is released with a certain speed in the horizontal direction. Describe the motion and path of an electron in the field with the help of Fleming’s left-hand rule. (6 marks)

(b) The figure 3 below shows a top view of a security door, perhaps in a bank. Study carefully the diagram and explain the mechanism of opening the door when the security officer presses a switch to let a customer in a bank. Also explain the function of the springs.  (6.5 marks) Figure 3: A door lock

10. A beam of high velocity electrons in a vacuum tube is directed towards a piece of tungsten embedded in a block of copper.

(a) Give an account on energy changes which takes place on impact. (3 marks)

(b) How and why should the apparatus be suitable shielded? (5 marks)

(c) Why it is necessary to use a copper block? (4.5 marks)

(Use a single well labeled diagram to support your answers in a, b and c above)

11. (a) An alternating potential difference is applied across a semiconducting silicon diode.

(i) Sketch a suitable graph to show how the current passing through the diode in forward bias varies with the applied voltage. (3 marks)

(ii) Explain how two semiconducting diodes may be used to charge car accumulator by using 12V alternating voltage? Show the circuit diagram. (5.5 marks)

(b) Look and study carefully the two diagrams below. The bulb lights in only one of these circuits. Identify the circuit and explain why the bulb lights while in the other circuit does not. (4 marks) (i) (ii) Figure 4

LEARNINGHUBTZ.CO.TZFORM FOUR PHYSICS REGIONAL SERIES-16 YEAR-2022

THE UNITED REPUBLIC OF TANZANIA PRESIDENT’S OFFICE REGIONAL ADMINISTRATION AND LOCAL GOVERNMENT

MWANZA CITY JOINT EXAMINATION (NYEGEZI, BUTIMBA AND MKUYUNI WARDS)

FORM FOUR PRE - MOCK EXAMINATION-2021

031 PHYSICS

Time: 3 Hours       MAY, 2021

Instructions

1. This paper consists of section A, B and C with total of eleven (11) questions.
2. Answer all questions in section A and B and any two (2) questions in section C.
3. Cell phones are not allowed in the examination room.
4. Non programmable calculator and mathematical table are allowed in the examination room.
5. Where necessary the following constants may be used:
• Acceleration due to gravity g = 10 m/s2
• Specific heat capacity of water = 4200Jkg-1K-1
• Speed of light in air = • Speed of sound in air = • Pie (π) = 3.14

SECTION A (15 Marks)

Answer all questions in this section

1. For each of the items (i) – (x), choose the correct answer among the given alternatives and write its letter beside the item number. (10 marks @1 mark)

(i) The diagram below shows series of experiments performed by a student to determine the relative density of a cork that floats in water. Four reading of the spring balance were obtained. The relative density of the cork is given by;-

A. B. C. D. E. (ii) Diffusion occurs more quickly in a gas than in a liquid because;-

1. The liquid contains a layer on its surface
2. The gas contain semi-permeable membrane
3. The gas molecules is small in size compared to the liquid molecules
4. The adhesion is large than cohesion in gas compared to that in liquid.
5. The speed of molecules in gas is greater than in liquid.

(iii) In a loading a lorry a man lifts boxes each of weight 100N through a height of 1.5m, if he lifts 4boxes per minute, the average power the man is working is;-

1. 100
2. 10
3. 600
4. 37.5
5. 2250

(iv) In a process of charging by induction in static electricity;-

1. A conductor is rubbed with an insulator
2. A charge is produced by friction
3. Negative and positive charges are separated
4. A positive charge induces a positive charge
5. Electrons are sprayed into an object

(v) A magnetic needle, free to turn in a vertical plane, is suspended first at the earth’s south magnetic pole and then at a point on the magnetic equator. The respective angles between the needle and horizontal are:

1. 0o and 0o
2. 70o and 70o
3. 0o and 45o
4. 0o and 90o
5. 90o and 0o

(vi) The acceleration of a moving object may be found from

1. The area under its velocity-time graph.
2. The slope of the velocity-time graph.
3. The area under its distance-time graph.
4. The slope of the distance-time graph.
5. The slope of the peak of its distance-time graph.

(vii) Which of these resources of energy is non-renewable?

1. Wave energy
2. Bio fuels
4. Fossil fuel
5. Geothermal energy

(viii) A typist uses a new carbon paper under her top typing paper for making a copy of a letter. When she holds the carbon paper close to a plane mirror, she can read the letter. This is because the mirror;

1. Forms an image the same size as object
2. Produces an inverted image
3. Produces a laterally image
4. Forms a virtual image
5. Forms an image behind the mirror.

(ix) Light waves differ from sound waves because;

1. Light is an electromagnetic wave
2. Light wave are long and sound waves are short
3. Interference is obtained with light waves but not with sound waves.
4. The speed of light is independent of the medium in which it travels
5. Sound waves do not travel in water

(x) The layer in the atmosphere where weather phenomena are formed is;-

1. Stratosphere
2. Magnetosphere
3. Troposphere
4. Thermosphere
5. Exosphere

2. Match the items in List A with the responses in List B by writing the letter of the corresponding response beside the item number in the answer sheet provided.

 LIST A LIST B (i) Longitudinal wave (ii) Reverberation (iii) Snell’s law (iv) Critical angle (v) Principle of superposition Sin over Sin Refractive index Water waves Sound wave Angle of incidence for which the angle of refractive is 900 Rise and fall of sounds of two vibrating objects The resultant displacement at any point is equal to the sum of displacements of different waves The multiple reflection of sound waves Angle of reflection for which the angle of incidence is 900

SECTION B (60 Marks)

Answer all questions from this section

3. (a) A body dipped in a liquid experiences an upthrust. Explain three factors on which the upthrust depends. (4.5 marks)

(b) Two identical free running trolleys are on a smooth horizontal runway. One trolley is at rest and the other approaches it at constant speed of 20m/s.

(i) Use the principle of conservation of momentum find the common speed of two trolleys after the collision. (3.5 marks)

(ii) Why the kinetic energies before and after the collision are different? (2 marks)

4. (a) A uniform half metre rule is balanced at 15cm mark when a load of 0.4N is hanging at the zero mark. Draw a sketched diagram indicating the arrow of weight of the rule acting through the centre of gravity hence determine the weight of the half metre rule (5 marks)

(b) A screw jack has a screw pitch of 5mm and the effort arm of 16cm .

(i) State two forms of energy in which the energy supplied to the screw jack is finally converted to.(2 marks)

(ii) Determine the percentage efficiency of this screw jack, if it needs an effort of 30N to lift a load of 750N.(3 marks)

5. (a) State one example of the use of a convex mirror and indicate why it is preferred to a plane mirror. (4 marks)

(b) An object is set 20cm in front of a lens and the real, inverted, magnified and at great distance image was formed. State the type of the lens used and determine the value of focal length.

(6 marks)

6. (a) Describe how a lens camera operates the same as human eye. Give three points. (6 marks)

(b) A 42kg refrigerator is placed on the back of a stationary pick-up. The coefficient of static friction between the refrigerator and the pick-up bed is 0.44. At what rate can the pick-up accelerate without the refrigerator sliding off the back? (4 marks)

7. (a) The diagram below show a bimetallic thermostat used to regulate a cooler and heater in a class room. It consist a brass of linear expansivity and iron of linear expansivity . To keep the temperature in the room constant, which of the two devices A or B should be the heater? Explain your answer.

(5 marks) (b) Three beakers are of identical size and shape; one beaker is painted matt black, one is dull white and one is gloss white. The beakers are filled with boiling water.

(i) In which beaker will the water cool most quickly? Give a reason. (3 marks)

(ii) State a process in addition to conduction, convection and radiation, by which heat energy will be lost from the beaker. (2 marks)

8. (a) A pressure cooker will cook beans faster than an open saucepan. Give explanation on these observations.(5 marks)

(b) An insulated cup holds 0.3kg of water at 0oC. 0.2kg of boiling water at standard pressure is poured into the cup. What will be the final temp (5 marks)

SECTION C (25 Marks)

Answer two (2) questions from this Section

9. (a) A boy has a large number of coloured bulbs labeled 240V and 60W, he wishes to use for decoration so that the bulbs operates normally. How many can he connect to a 240V and 5A fuse? (4 marks)

(b) You are required to use 3Ω resistor in your electric circuit. Unfortunately there are only 2Ω resistors in School Physics laboratory. How could you design the required resistor from available resistors? (4.5 marks)

(c) A figure shows a block diagram of generation and distribution of electricity using a.c generator. Study the diagram then answer the questions that follow. 1. What will be the main item of equipment in the sub-stations A and B? (1 mark)
2. If the transformer T has 80 turns on its primary coil how many turns must it have on its secondary coil? (3 marks)

10. (a) A piano wire and a turning fork produce different notes at the same time and beats are heard. What could be done on the piano wire in order to emit a note of the same frequency as vibrating fork.(Give three points) (3 marks)

(b) A graph below shows a wave emitted by the electromagnetic source. If the velocity of the wave is 12m/s, determine the frequency and the wavelength of the wave. (5 marks)

(c) Boats use “sonar” to detect the depth of water in the seas or lakes. A sonar pulse sent out by a boat arrives back after 3seconds. If the speed of sound in water is 1500m/s, how deep is the water (4.5 marks)

11. (a) Why some semiconductors called ‘P’ type and other ‘N’ type? (3 marks)

(b) Describe, how you will connect the semiconductor diode as forward bias. (4 marks)

(c) The diagram bellow shows a puzzle box contains two lamps and simple components so that when T1 is connected to the anode lamp L1lights but when terminal T2 is connected to the anode, lamp L2 light. Suggest what the puzzle box is and how the connections are made. (5.5 marks) LEARNINGHUBTZ.CO.TZFORM FOUR PHYSICS REGIONAL SERIES-70 YEAR-2021

THE PRESIDENT’S OFFICE REGIONAL ADMINISTRATION AND LOCAL GOVERNMENT

KILOSA DISTRICT COUNCIL

MIKUMI - CLUSTER ACADEMIC UNITY (MAU)

FORM FOUR PRE - MOCK JOINT EXAMINATION

032/1 PHYSICS 1

(For School Candidates Only)

TIME: 3 Hours Wednesday March 17, 2021

INSTRUCTIONS

1. This paper consists of sections A, B and C with a total of eleven (11) questions
2. Answer all questions in section A and B and two(2) questions from section C
3. Whenever calculations are involved show your work Cleary
4. cellular phones and any authorized materials are NOT allowed in the examination room
5. Non programmable calculator may be used

If necessary the following constants may be used

1. Acceleration due to gravity, g = 10m/s2
2. Pie , π = 3.14
3. Resistivity of steel = 10.5 x 10-8 Ωm
4. At STP the pressure of oxygen and nitrogen = 1.013 x 105 Pa
5. At STP temperature of oxygen and nitrogen =0°C = 273K
6. Density of water = 1g/cm3 or 1000kg/m3

SECTION A (15 MARKS)

Answer all questions in this section

1. For each of the items (i) – (x), choose the correct answer from among the given alternatives and write its letter beside the item number in the answer sheet provided (10 marks) i. Which among of the following is a dwarf planet?

1. Mercury
2. Saturn
3. Neptune
4. Pluto

ii. In the resolution of vectors which mathematical method is used?

1. Pythagoras theorem
2. trigonometric ratio
3. set theorem
4. logarithm

iii. When a body sliding on an inclined plane its coefficient of dynamic friction can be given as

1. Tan θ
2. Sin θ
3. Cos θ
4. mgcos θ

iv. Film in a lens camera is compered to …………….in human eye

1. Iris
2. Retina
3. Lens
4. Pupil

v. An instrument used to identify the presence of electric charge on an object is called

1. Telescope
2. barometer
3. gold-leaf electroscope
4. Vernier caliper

vi. Decreasing in velocity or slowing down of velocity per unit time is called

1. Acceleration
2. Retardation
3. Speed
4. velocity

vii. The SI Unit of average velocity is the same as the SI Unit for…….

1. Length
2. Acceleration
3. Speed
4. Displacement

viii. An object has density of 7g/cm3. What is its relative density

1. 5

ix. A stone of 2Kg falls from a height of 25m above the ground. Calculate the potential energy possessed by the stone

1. 500J
2. 270J
3. 520J
4. 390J

x. A steel bar has a length of 2.3m and diameter of 2 x 10-5 m. what is resistance?

1. 768.27 Ω
2. 668.72 Ω
3. 768 Ω
4. 769 Ω

2. Match the regions of atmosphere in LIST A with their corresponding characteristics in LIST B by writing the letter of the correct response beside the item number in the answer sheet provided (5 marks)

 List A List B i. Troposphere ii. Stratosphere iii. Mesosphere  iv. Thermalsphere v. Exosphere The region where satellites obit the earth. The region with ozone layer The region where clouds and rain are formed Allow radio communication over long distances The region where planes fly The region with the sun The region where most meteors burn while entering the earth’s surface

SECTION B (60 MARKS)

Answer all questions in this section

3. (a).A plane mirror and concave mirror both they produce an image from the given object. Draw the diagram to represent the formation of image in each case (for the concave mirror consider an object to be at the center of curvature, (C). Hence show two similarities and two differences of images formed. ( 6 marks)

(b) Explain the formation of mirage (4 marks)

4. (a) A heavy uniform beam AB of weight 500N is supported at its ends. The beam carries a weight of 3000N at a distance of 1.5m from the end A. if the beam is 4m long. Find the thrust at A and B (6 marks)

(b) Machine is a device used to simplify work. With example explain how the following simple machines do they simplify work in their respective stated area. (4 marks)

1. Inclined plane at home
2. Screw jack in garage

5. (a) Explain four (4) factors affecting resistance of a conductor. (6 marks)

(b) Describe two (2) defects of simple cell (4 marks)

6. (a) Explain what happens when water in a container heated? (4 marks)

(b) A sample of oxygen gas has a volume of 0.11 m3 at a temperature of 12°C and a pressure of 8.1 x 105 Pa while a sample of nitrogen gas has a volume of 0.18 m3 at a temperature of 22°C and a pressure of 1.03 x 105 Pa. Which gas will have the larger volume at STP? (6 marks)

7. (a) A diagram below illustrates part of the displacement-time graph of a wave travel with velocity of 2m/s. calculate the amplitude, Frequency and Wave length (6 marks) (b) With their function identify any four main parts of ripple tank (4 marks)

8. (a) With the help of separate diagram explain how three radiations emitted by radioactive elements are affected in electric plates and magnetic plates (6 marks)

(b) A radioactive element has an initial count rate of 1200 counts per minutes measured by a scale and this falls to 150 counts per minute in 15hours. Determine the half-life of the element (4 marks)

SECTION C (25 MARKS) Answer two (2) questions from this section

9. (a) When a simple pendulum displaced at a small angle swings to and fro, in this motion potential energy and kinetic energy changes by alternating each other. With the aid of diagram verify the alternation of these energies. (8.5 marks)

(b) A 50kg girl runs up a staircase of 50 steps each step is 15cm in height in 5s. Find Work done against gravity by the girl and Power she use to run (4 marks)

10. (a) state laws of electromagnetic induction (4.5 marks)

(b) With reasons name the following symbols. Hence state the function of each in the national grid of electricity (8 marks)

 (i) (i) 11. (a) Draw a well labelled diagram of cathode ray tube. Hence state two uses of the drawn diagram and two properties of rays produced in it. (8.5 marks)

(b) What are the main purpose of connecting a diode and transistor on various electronic devices? (Describe for each device) (4 marks)

LEARNINGHUBTZ.CO.TZFORM FOUR PHYSICS REGIONAL SERIES-51 YEAR-2021

THE PRESIDENT’S OFFICE MINISTRY OF EDUCATION, REGIONAL ADMINISTRATION AND LOCAL GOVERNMENT

ARUSHA REGIONAL MOCK EXAMINATION-MAY 2021

PHYSICS

FORM FOUR

INSTRUCTIONS

1. This paper consists of section A, B and C.
2. Answer all question in section A and B and ANY TWO (2) question from section C
3. All work should be shown clearly on each question in systematic manner
4. Mathematical table and non-programmable calculators may be used
5. Cellular phones and any unauthorized materials are NOT ALLOWED in the examination room.
6. Write your examination number at the right corner of every page of answer sheets provided
7. When ever necessary the following constants may be used.
• Acceleration due to gravity g = 10m/s2 or ION/ kg
• Pie, π= 3.14
• Density of water = lg/cm3 or 1000kg/m3
• Velocity of sound in air = 340m/ s
• Velocity of sound in water = 1500m/ s

SECTION A (15 MARKS)

1. Choose the most correct answer and write its letter besides its alternatives number it answer sheet/ booklet(s) provided

(i). . . . . . . . . Is the area around a magnet current carrying conductor where magnetic strength can be detected by compass

1. Magnetic domain
2. Magnetic field
3. Magnetic poles
4. Induced field
5. Neutral point

ii. Which of the following apparatus is used for measuring the volume of irregular solid?

1. Pipette
2. Beaker
3. Measuring tape iii.
4. Measuring cylinder
5. Burette

iii. A suspended magnetic needle always comes to rest with axis in a vertical plane called

1. Geographic meridian
2. Magnetic declination
3. Magnetic meridian
4. Geographic North pole
5. Geographic declination

iv. A body weights 3.6N in air and 2.4N when immersed totally in water. The density of the body in g/cm3 is

1. 0.40g/cm3
2. 1.40g/cm3
3. 3.OOg/cm3
4. 2.00g/cm3
5. 0.33g/cm3

v.A dish of liquid is left on a laboratory bench, some of the liquid evaporates, what happens and why?

1. The liquid cools, because liquid molecules have more potential energy than gas molecules
2. The liquid cools because faster moving molecules escape
3. The liquid warms because liquid molecules have less potential enerærr than gas molecules
4. The liquid warms because slower moving molecules are left behind
5. None of the above

vi. Which particle is emitted by a hot metal filament?

1. Alpha particle
2. Neutrons
3. Electrons
4. Protons
5. Beta particle

vii. When Fleming's left hand is applied to a motor the thumb points in the direction of

1. Field
2. Current
3. Motion
4. Wire
5. Fingers

viii.When an electric heater is stamped 240v, 60w is to be used in a 240v mains, the resistance of the heater is:-

1. 960Ω
2. 96Ω
3. 9.60Ω
4. 0.96Ω
5. 9600Ω

ix. The best way of testing the strength of a magnet is

1. Republsion
2. Attraction
3. Harm
4. Induction
5. Heating

x. When secondary colour is mixed with a primary colour the result is a complementary colour. Which of the following colors is complementary to magenta?

1. Green
2. Red
3. Blue
4. Cyan
5. Yellow

2. Match each of the statement in List B. with appropriate word/prase in List A by writing the letter of the response beside the item number in answer sheets/ booklet(e) provided

 LIST A LIST B i) Primary Rainbow  ii) Complementary colour  iii) Subtractive mixing of colors  iv) Primary color v) Addictive mixing of colors Blue, magenta Red, cyan cyan, magenta, yellow It decreases wave length from total mixture When two primary colors are mixed the colour are subtracted from white light and the mixture becomes black When two rim colors combine to form white It increases the wave length present Is formed as a results of light that has undergone two total internal reflection in water droplet.  Is formed as a results of light that has undergone one total internal reflection in water droplet.

SECTION B (60 MARKS)

Answer ALL question in this section

3. a) A cube of wood of side 5.0cm and density 600kgm-3 is placed in water

i. What fraction of the volume of the wood would be immersed in water?

ii. What force must be applied to the cube so that the top surface of the cube is on the same level as the water surface?

b) A passenger ferry boat with vertical sides has a water-line area of 1500m2. When fully loaded with passengers it sinks by 0.6cm. If the average mass of a passenger is 60kg. Calculate the number of passengers on boat.

4. a) Use a well labeled diagram to explain the working principle of a hydraulic press in a simple machine

b) A uniform pencil AB weighing 40g can be balanced horizontally on a knife edge at 2cm from the end A when a mass of 60g is hung from this end. What is the length of a pencil?

5. a) Electrical energy is distributed in all parts of Tanzania by the National grid system  which transmits a.c at very high voltage

1. explain why a very high voltage is necessary
2. why is an a.c and not a d.c used?
3. State the advantage the National Grid has over the power station distributing power in the neighboring area directly.

b) The National Electric company (TANESCO) sells electric energy at Tsh. 435 per unit kilowatt/ hour. Calculate the cost of using, a 3kW electric heater and 1500W shaving machine in a barbar shop simultaneously for 10 minutes.

6. a) i) Describe an experiment to show that sound can not travel in a  vaccum

ii) Why are echoes not formed in class rooms?

iii) How are unwanted echoes example in concert halls eliminated?

b) A drum at station A is connected to a wire at station B. A man at A beats the drum while another person at B places his ear at the wire and hears two sounds separated by a time interval of 0.5 seconds. How far a part are the two men? If the velocity of sound in string is 5280m/s

7. a) Explain briefly how heat losses have been prevented in a vaccum flask.

b) i) Ice is heated from a temperature of -50C to water at 150C. Sketch a graph to show the variation of its density with temperature.

ii) Describe a Simple experiment you can perform in the laboratory to demonstrate that solids expands when heated.

iii) The figure below shows two bulbs A and B painted black and silver respectively. What would you expect to happen if the heater is switched on, given that the bulbs contain air.  Explain. 8. a) i) Define critical angle

ii) Find the refractive index from air to water if refractive index from water to air is 0.75

b) Carefully study the figure below and answer the following questions i. Give the name of the figure above ii. Label the parts A, B, C, D, E, and G iii. State the functions or part labeled D, E and B iv. Describe the nature of the image formed.

SECTION C (25 MARKS)

Answer two (2) questions from this section

9.(a) Describe impulse of a force and state its Sl unit

(b) A voleeyba]l A of mass 0.3kg is moving on the ground at a speed of 4ms-1 towards a football B which is at rest on the ground and has a mass 0.2kg. when A collides with B, the balls remain in contact for 0.2sec. after the collision B moves with a velocity of  1.8ms-1 in the opposite direction with A. Find

1. the velocity of A after the collision
2. the average force of A and B during the collision

c) State the relationship between the total kinetic energy of the system before and after the collision

10. a) Distinguish between the following:

i) Hard x-ray and soft x-ray

b) A radon 22280 Rn emits α- particles followed by a β - particles. What are the atomic number and mass number of the nucleus formed after the emission?

c) A radioactive source has a half life of 16 days. How long will it take for the count rate to fall from 160 counts per minutes to 20 counts per minute?

d) Mention layer of the Earth and it importance

11. a) Define the following:

1. A capacitor
2. An inductor
3. Transistor Fig. 01

b) Use the sketch below (fig 01) to answer the following

1. What do symbol B, C and E represents?
2. What types of the device does the sketch represent?
3. Write down the current relation for the device
4. What type of a device does the sketch below (fig. 02) represent? Fig. 02

v. Give the main difference between a device of fig. 01 and fig. 02

c) Draw a circuit for voltage amplification.

LEARNINGHUBTZ.CO.TZFORM FOUR PHYSICS REGIONAL SERIES-24 YEAR-2021

### For Call,Sms&WhatsApp: 255769929722 / 255754805256 ## WHATSAPP US NOW FOR ANY QUERY

GO TO NECTA EXAMS