PRESIDENT’S OFFICE REGIONAL ADMINISTRATION AND LOCAL GOVERNMENT
COMPETENCY BASED EXAMS
SECONDARY EXAMINATION SERIES
FORM THREE MID TERM-2 EXAMINATION
031 PHYSICS
TIME : 3HRS AUG,2023
INSTRUCTIONS
SECTION A (15 MARKS)
Answer all questions in this section
i. Which property of a concave mirrors is suitable for a dentist to consider when selecting concave mirrors for repairing dental related activities?
ii. Why is mercury preferred in clinical thermometer as a thermo metric liquid as compared to water and alcohol?
iii. When a plastic pen is rubbed against a dry hair, the pen attracts small pieces of paper. This means that
iv. Which of the following statements is correct when the resistance “R” if a wire is measured using an ammeter, voltmeter and Rheostat?
v. A form three student wishes t check the upper fixed point and the lower fixed point on Celsius scale thermometer. The student has four beakers namely P, Q R and S
P- Contains a mixture of boiling salt solution
Q- Contains a mixture of ice and water
R- Contains a mixture of ice and salt
S- Contains boiling water
Which beaker should a student use to check the fixed points?
vi. Refractive index of glass block cannot be evaluated from the following relation-
vii. A force prevents a body from sliding is called?
viii. A stone is thrown from the top of a building 45m high at a speed of 12m/s. How long does it take to reach the ground?
ix. Racing cars rarely gets accident despite their high speed because they-
x. “Extension of material is proportional to force applied” where is this statement belongs?
2. Match the items in list A response to list B by writing the letter of the correct response beside the items number in your answer booklet provided
LIST A | LIST B |
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SECTION B (60 MARKS)
Answer all questions in this section
3. a)i) A form three students from a certain school was unable to know the rules of locating an image by using converging mirror. List three rules that will help the students to locate an image when an object is placed in front of converging mirror perpendicular to its principal axis.
ii) A concave mirror is used to form an image of a pencil with the same size as a pencil’s objects. By using a well labeled diagram show the position of the image and state its characteristics.
b) A ray of light is travelling from air to water make an angle of incidence of 60o given that the refractive index of water is 4/3, what is the angle of refraction of the ray of light?
4. a)i) What is the turning effect of a force?
ii) How can the moment of a force be increased considerably in practical life? Give two examples.
b) i) Briefly explain why the handle of a door is near to its outside edge?
ii) A uniform meter ruler AB is pivoted at a distance of 80cm from end B. If 20g mass hang at end B. At what distance from end A must 100g mass hang on a meter rule in order to balance the rule horizontally? (Neglect the mass of the rule).
5. a) i) Distinguish between light spectrum and dispersion of light.
ii) Briefly describe how a light ray passes through an equilateral glass prism.
b) Figure below represents three primary colours combined together and answer the questions that follow
6. a) Suppose you are given a bar magnet whose poles are not located. Briefly explain how you can determine which end of a bar is the North pole in the laboratory.
b) Explain the meaning of magnetic shielding.
c) Draw the following diagram.
7. a) State the relationship between pressure, force and area.
b) Explain why one feels not comfortable when he/she lift a bucket of water by its handle made of thin metal. What will be the pressure experienced if the handle is made of thicker metal?
c) The mss of the cube is 120kg, if it measures 50cm x30cm x20cm, what is maximum pressure that it can exert?
8. a) A positively charged rod is brought near body A and B if body A is at a distance of 1cm and body B is a distance of 3cm, which of the two bodies will be attracted more?
b) i) What happens when two positively charged bodies brought into contact?
ii) Explain why a pieces of paper attracted by a plastic charged pen after few seconds fell off?
SECTION C (25 MARKS)
Answer any two questions from this section
9. a) A resistor of 4Ω is connected in series with two bulbs of 3Ω and 6Ω connected in parallel. If two cell (battery) of 3V is connected across the circuit.
i) Draw the circuit diagram to show the arrangement.
ii) What is the P.D across the 3Ω bulb?
b) What is the advantage of parallel arrangement of a bulbs over series arrangement during electric installation at home.
10. a) i) State the law of flotation.
ii) Mention two conditions that can make an object to float.
b)i) Why hydrometer contain a large number below and small number above.
ii) Draw a well labeled diagram of Hydrometer.
c) A body weight 0.8N in air and 0.5N when completely immersed in water. Calculate,
11. a) Car A is moving with a velocity of 20m/s while car B is moving with a velocity of 30m/s. Calculate the velocity of car B relative to car A if,
b) i) What is resolution of a force?
ii) Figure below shows a block being pulled along a horizontal surface. If a force of 20N is applied in direction of A at an angle of 60o. What is the resolved part of the force in direction B?
FORM THREE PHYSICS EXAM SERIES 146
FORM THREE PHYSICS EXAM SERIES 146
THE PRESIDENT’S OFFICE
REGIONAL ADMINISTRATIVE AND LOCAL GOVERNMENT
FORM THREE EXAMINATIONS SEPT 2022
NEW NECTA FORMAT
PHYSICS
PHYSICS FORM THREE
Where necessary use the following constants
Acceleration due to gravity (g) = 10m/s2
Density of water = 1g/cm3/ 1000kg/m3
ATTEMPT ALL QUESTIONS IN THIS SECTION
LIST A | LIST B |
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SECTION B (60 MARKS)
ATTEMPT ALL QUESTIONS IN THIS SECTION
(b)A convex mirror of focal length 15cm is used to produce an image an object placed 20cm from the pole of the mirror
Find the position and nature of the image formed
(b)A bird is plying at 80/km/hr. due East relative to the air. A wind is blowing at 30km/hr in the north East direction as seen from the ground. What is the velocity of the bird relative to the observer on the ground?
(c) Identify three ways of reducing friction force acting on a body
(b)A uniform beam of mass 50kg and length 6m is supported by two vertical strings at A and B such that each pant is 0.5m from each end A mass of 40kg is also hung at m from A. Find the tension in the strings at points A and B
(ii) Explain the important of the following on a hydrometer
(b) A cube of side 10cm and mass 400g floats in water
(b)A compound microscope has objective lens of focal length 8cm and eyepiece lens of focal length 4cm the distance between the lenses is 28cm. the lens is adjusted such that the final image is at infinity
(b)A wheel and exle has wheel radius of 20cm and axle radius of 5cm. The efficiency of the machine is 90%
SECTION C
ATTEMPT ANY TWO QUESTIONS IN THIS SECTION
(b)The figure below shows a bimetallic strip having two metals invar and brass. (Brass has a higher linear expansitivity than invar)
Explain how the bar will bend if it is heated to a higher temperature than room temperature
(c) A telegraph wire has a length of 30m and is made of metal of linear expansitivity 0.00002/K
Find the change in length from a hot day temperature 30°C to a very cold day - 5°C
(b)Explain why coefficient of Kinetic friction is always smaller than coefficient of state friction
(c)Three forces act on a body as shown below
Find the value of T and F
(b)Convex mirrors are always used as driving mirrors. With the aid of a diagram explain why these kinds of mirrors are used in this case
(c)What is the maximum magnification produced by a convex lens of local length 5cm.
FORM THREE PHYSICS EXAM SERIES 95
FORM THREE PHYSICS EXAM SERIES 95
THE PRESIDENT'S OFFICE
MINISTRY OF REGIONAL GOVERNMENT AND LOCAL GOVERNMENT
MID TERM EXAMINATION
PHYSICSFORM-3
2021- AUG/SEPT
TIME: 2:30 HRS
Instructions
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 booklet provided.
(i) A bar of copper is heated from 293 K to 333 K. Identify a false statement among the following:
(ii) Which among the following is not a property of magnetic lines of force due to a bar magnet?
(iii) When an object moves around a horizontal circle of centre O with a constant speed, its acceleration will be
(iv) The image formed by plane mirrors are always
(v) The battery in the circuit shown in the following diagram has an e.m.f. of 2 V and negligible internal resistance.
What will be the current flowing in the 6 ? resistor?
(vi) A body is said to be in equilibrium IF
(vii) Tow forces of 5 N and 8 N are acting at the same point and are inclined at an angle of 45° to each other. What will be their resultant force?
(viii) A solid metal cube has each side doubled to make a solid cube of the same metal eight times bigger in volume. The ration of resistivity of the new cube to resistivity of the old cube is
(ix) A green card with red flowers when viewed in a red light will appear:
(x) Colours are produced when white light passes through glass prism because
2. Match the following items.
List A | List B |
(i) Ability to oppose flow of current (ii) Path around which electrons can flow (iii) Wire with high potential difference relative to other wires in a cable (iv) Wire dipped into ground near home to protect appliances (v) Work done by moving unit of electricity from one point to another |
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SECTION B (60 Marks)
Answer all questions in this section.
3. (a) In a light experiment, a narrow beam of light directed onto a glass prism leaves the prism and falls on a white screen. Draw a labelled diagram to show the experimental set-up and observation seen on a screen.
(b) Explain two ways in which lens cameras differ from human eye.
4. (a) Briefly explain why hydrometer
(i) is weighed with lead shots.
(ii) has a narrow stem.
(b) A piece of rubber of volume 100 cm3 and the density of 0.45 g/cm3 floats in water. Calculate:
(i) The volume of rubber that partially immersed in water.
(ii) The force required to immerse the rubber completely.
5. (a) List four factors which affect the rate of evaporation of liquids.
(b) (i) Define relative humidity.
(ii) Calculate the relative humidity given that the reading on dry bulb hydrometer is 24°C and the wet bulb temperature reading is 16°C.
6. (a) (i) What peculiar property does the effort has in all classes of levers?
(ii) A metre rule of weight 1.0 N is supported horizontally on two knife edges each placed 10.0 cm from its ends. If the weight of 1.5 N is placed at its mid-point, calculate the reaction at the supports.
(b) (i) State the law of floatation.
(ii) Find the fraction of the cork that partially immersed when a piece of cork of density 0.25 g/cm3and a mass of 20 g floats in water.
7. (a) Write down the second and third equations of motion in a straight line.
(b) Explain the following terms as they are applied in motion in a straight line:
(c)A stone is thrown vertically upwards with an initial velocity of 50 m/s.
(i) Calculate the time that the stone will take to return back to the thrower.
(ii) What will be the maximum height reached?
8. Three resistors of 2 Ω, 4 Ω and 6 Ω are connected in series to a battery of e.m.r 24 V and have negligible internal resistance.
(a) Draw the circuit diagram including the battery, ammeter, switch and the three resistors.
(b) Find the current flowing in the circuit drawn in 8 (a) above.
(c) Find the potential difference at the ends of each resistor in 8 (a).
SECTION C (25 Marks)
Answer two (2) questions from this section
9. (a) A beaker containing ice is heated from -5°C to 0°C and then from 0°C to 15°C. With the aid of a diagram, explain the variation of density with temperature.
(b) A brick at 20°C has a dimension of 30 cm, 18 cm and 10 cm for length, width and height respectively. If a brick is heated to a new temperature of 150°C, calculate the new dimensions.
10.(a) State two conditions for a body to be in equilibrium.
(b) Distinguish between centre of mass and centre of gravity.
(c) A uniform metre rule AB is balanced horizontally on a knife edge placed 5cm from B with a mass of 60g at B. Find the mass of the ruler.
11. (a) Define the word coulomb.
(b) States Ohms law.
(c) Two resistors of 30 and 60 are connected in parallel to a 3V battery.
(i)Draw the schematic diagram.
(ii)Find the effective resistance of the circuit.
(iii)Calculate the current passing through the 60 resistor.
FORM THREE PHYSICS EXAM SERIES 62
FORM THREE PHYSICS EXAM SERIES 62
THE PRESIDENT'S OFFICE
MINISTRY OF REGIONAL GOVERNMENT AND LOCAL GOVERNMENT
AUGUST-SEPTEMBER EXAMINATION SERIES
PHYSICS FORM-3
2020
TIME: 2:30 HRS
Instructions
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 booklet provided.
(i) Which pairs of instruments would you use to correctly measure the diameter of a small ball bearing?
(ii) When the sun shines on the dark-coloured driving wheel of a car, the wheel feels warm. Why?
(iii)Which one is a characteristic of a plane mirror?
(iv)What role does the iris play in the human eye?
(v) The correct arrangement of metals in ascending order of their linear expansivities is?
(vi) The suspended magnetic needle always comes to rest with its axis in a vertical plane called?
(vii) Which of the following is the correct weight of a body of mass 48 g when placed on the moon surface?
(viii) A car moving at steady speed has a frictional force on its surface whose size depends on its
(ix) The image formed by plane mirrors are always
(x)Lenz’s law can be applied to predict the
2. Match the items in List A with responses in List B by writing the letter of the correct response beside the item number in the answer booklet provided.
LIST A | LIST B |
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SECTION B (60 Marks)
Answer all questions in this section.
3. (a) Why a bubble of air increases in volume as it rises from the bottom of a pond of water to the surface? Briefly explain.
(b) A half meter rule AB is freely pivoted at 18 cm from end A and balances horizontally when a body of mass 35 g is hung 48 cm from end B. Calculate the mass of the rule.
4. (a) Briefly explain why hydrometer
(i) is weighed with lead shots.
(ii) has a narrow stem.
(b) A piece of rubber of volume 100 cm3 and the density of 0.45 g/cm3 floats in water. Calculate:
(i) The volume of rubber that partially immersed in water.
(ii) The force required to immerse the rubber completely.
5. (a) Give two examples which illustrate the rectilinear propagation of light.
(b) (i) The refractive index of light passing from water to air is 3/4. Calculate the critical angle. (ii) Outline two differences between primary and secondary rainbows.
6. (a) (i) What is the essential of kinetic theory of matter?
(ii) Sketch a graph showing how force applied in a stretched string varies with its extension.
(b) (i) State Hooke’s law.
(ii) List two applications of gamma rays.
7. (a) (i) Define turning effect of force and give its SI unit.
(ii) How the moment of force can be increased considerably in practical life? Give two examples.
(b) (i) List two factors that affect stability of a body
(ii) Briefly explain why the handle of a door is near its outside edge?
8. (a) (i) Distinguish between light spectrum and dispersion of light.
(ii) Briefly describe how a light ray passes through an equilateral glass prism.
(b) Study Figure 1 which represents three primary colours combines together and answer the questions that follow.
SECTION C (25 Marks)
Answer two ( 2) question from this section.
9. (a) (i) What is meant by the term thermal expansion?
(ii) Mention two applications of thermal expansion of solids.
(b) (i) List three areas where bimetallic strips are used.
(ii) Why a bimetal strip made of brass and invar is curved outside with brass?
(c) Describe how simple fire alarm system operates.
10. (a) (i) Distinguish between primary and secondary cells, giving one example of each.
(ii) Identify two defects of a simple cell.
(b) (i) Explain why lead – acid accumulators are used in car batteries rather than dry cells?
(ii) A cell of unknown e.m.f, E and internal resistance 2? is connected to a 5? resistance. If the terminal p.d, V is 1.0V. Calculate the e.m.f, E of a cell.
(c) (i) List two devices that are important when checking electrical faults in domestic appliances.
(ii) Briefly explain why a very high voltage is necessary when transmitting electrical energy from power station?
11. (a) (i) What is meant by impulse of a force?
(ii) Briefly explain why seat-belts are designed to stretch in a collision.
(b) i) Define momentum.
(c)A car of mass 2000 kg is travelling along a straight road at a constant velocity of 10 m/s developing 3.0 kilowatts. If the engine of the car is switched off:
FORM THREE PHYSICS EXAM SERIES 30
FORM THREE PHYSICS EXAM SERIES 30