1. What is the mechanical transfer of energy by an external force on a system called?
a) Power
b) Work
c) Force
d) Intensity
Answer: b

2. In a water-lifting electric pump, which energy conversion takes place?
a) Electrical energy to potential energy
b) Kinetic energy to electrical energy
c) Kinetic energy to potential energy
d) Electrical energy to kinetic energy
Answer: a

3. A dynamo converts:
a) Mechanical energy to electrical energy
b) Electrical energy to mechanical energy
c) Electrical energy to magnetic energy
d) Magnetic energy to mechanical energy
Answer: a

4. A flying jet possesses:
a) Potential energy
b) Kinetic energy
c) Wind energy
d) Both kinetic and potential energy
Answer: d

5. When a ball is thrown vertically upwards, which quantity remains constant during motion?
a) Displacement
b) Velocity
c) Acceleration
d) Energy
Answer: c

6. When the speed of a moving object is halved, its kinetic energy becomes:
a) ¼ of its original value
b) 4 times its original value
c) No change
d) Acceleration is doubled
Answer: a

7. A bullet is fired from a recoiling rifle. The ratio of kinetic energy of the rifle to that of the bullet is:
a) Zero
b) One
c) Less than one
d) Greater than one
Answer: c

8. A moving neutron collides with a stationary alpha particle. What fraction of its kinetic energy is lost?
a) 1/4
b) 1/16
c) 9/25
d) 16/25
Answer: d

9. In a spring of a wristwatch, the stored energy is:
a) Kinetic energy
b) Potential energy
c) Heat energy
d) Chemical energy
Answer: b

10. In a rechargeable cell, which form of energy is stored?
a) Electrical energy
b) Potential energy
c) Chemical energy
d) Kinetic energy
Answer: c

11. Commercially, the energy produced from coal is called:
a) Light energy
b) Kinetic energy
c) Thermal energy
d) Potential energy
Answer: c

12. What is the SI unit of heat energy?
a) Joule
b) Newton
c) Calorie
d) Kelvin
Answer: a

13. What is the SI unit of Young’s modulus of elasticity?
a) dyne/cm
b) newton/m
c) newton/m²
d) m²/s
Answer: c

14. Ampere is the SI unit of:
a) Electric current
b) Magnetic field
c) Electric charge
d) Resistance
Answer: a

15. Energy is lost as heat when a machine runs. This heat is caused due to:
a) Combustion
b) Burning
c) Friction
d) Lubrication
Answer: c

16. Which of the following is not a non-conventional source of energy?
a) Solar energy
b) Wind energy
c) Tidal energy
d) Natural gas
Answer: d

17. What is the primary reason stars have an inexhaustible energy supply?
a) Hydrogen fusion into helium
b) Helium fusion into hydrogen
c) Radioactive decay
d) Excess oxygen
Answer: a

18. Which energy conversion occurs using a photovoltaic cell?
a) Solar to thermal energy
b) Solar to mechanical energy
c) Solar to electrical energy
d) Solar to optical energy
Answer: c

19. Which of the following is false regarding a photovoltaic cell?
a) It’s another name for a solar cell
b) It can act as an infrared detector
c) It stores light energy as electricity
d) It converts electric energy into light energy
Answer: d

20. Which energy source contributes the most to electricity generation in India?
a) Atomic energy
b) Thermal energy
c) Hydro energy
d) Wind energy
Answer: b

21. When an object is lifted to a height of 3 m and dropped onto a 1 m high table, which is correct?
a) Potential energy decreases by two-thirds of the total energy
b) Potential energy decreases by one-third
c) Kinetic energy increases by two-thirds, potential energy increases by one-third
d) Kinetic energy increases by one-third, potential energy decreases by one-third
Answer: a

22. When a swing moves upward from rest, what happens?
a) Potential energy decreases, kinetic energy increases
b) Kinetic energy decreases, potential energy increases
c) Both energies decrease
d) Both energies increase
Answer: b

23. Match the following physical quantities with their respective units:

Quantity	Unit
A. High speed	1. Mach
B. Wavelength	2. Angstrom
C. Pressure	3. Pascal
D. Energy	4. Joule

Code:
a) 2-1-4-3
b) 2-1-3-4
c) 1-2-4-3
d) 1-2-3-4
Answer: d