(ii) When an object moves around a horizontal circle of centre O with a constant speed, its acceleration will be

1. zero
2. towards the centre
3. away from the centre
4. along the tangent to the circle
5. along the direction of rotation.

(iii) A bar of copper is heated from 293 K to 333 K. Identify a 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.

(iv) The direction of heat flow between two bodies is determined by

1. the direction of the wind
2. the mass of each body
3. the temperature difference of the two bodies
4. the coefficient of cubical expansion of the bodies
5. the coefficient of linear expansion of the bodies.

(v) Refractive index of a glass block cannot be evaluated from one of the following ratios:

1. sin i to sin r
2. Velocity of light in air to velocity of light in glass
3. Frequency of light in air to frequency of light in glass
4. Wavelength of light in air to wavelength of light in glass
5. Real depth to apparent depth.

(vi) Which among the following is not a property of magnetic lines of force due to a bar magnet?

1. They have a direction from North Pole to South pole outside the magnet
2. They do not exist inside the magnet
3. They have a direction from South pole to North pole inside the magnet
4. They tend to be close inside the magnet but are wider apart outside the magnet 
5. They form complete loops.

(vii) When charging a body by friction, the particles which are transferred are

1. protons
2. nuclei and protons
3. nuclei
4. electrons
5. protons and electrons.

(viii) Which of the following statements is correct?

1. Electrons but not X­-rays are deflected by magnetic field
2. Electrons and X-­rays are both particles
3. Electrons are deflected by magnetic field but not by electric field
4. Electrons are heavy particles
5. Electrons and X­rays are both deflected by magnetic field.

(ix) Cathode rays are

1. a stream of energy
2. used to examine a complete machine without dismantling it
3. a stream of molecules
4. a stream of electrons
5. used to detect flaws and cracks in metal casings and welded joints.

(x) A transistor is a device which

1. amplifies alternating current or voltage
2. amplifies direct current or voltage
3. rectifies direct current or voltage
4. amplifies and rectifies alternating current or voltage
5. rectifies alternating current.