Work, Energy and Power- Objective Questions

6. The total work done on a particle is equal to the change in its kinetic energy. This is applicable-

• Always
• Only if the conservative forces are acting on it
• Only in inertial frames
• Only when pseudo forces are absent

7. Potential energy is defined – 

• Only in conservative fields
• As the negative of work done by conservative forces
• As the negative of work done by external forces when ΔK = 0
• All of these

8. A spring with spring constants ‘k’ when compressed by 1 cm, the potential energy stored is U. If it is further compressed by 3 cm, then the change in its potential energy is?

• 3U
• 9U
• 8U
• 15U

Read More ⇒ Physical Quantities and Measurements

9. Two springs have force constants K₁ and K₂ (K₁ > K₂). Each spring is extended by the same force F. If their elastic potential energy is E₁ and E₂ then E₁/E₂ is?

• K₁ / K₂
• K₂ / K₁
• v(K₂ / K₁)
• v(K₁ / K₂)

10. An unloaded bus can be stopped by applying brakes on a straight road after covering a distance x. Suppose, the passenger add 50% of its weight as the load and the braking force remains unchanged, how far will the bus go after the application of the brakes? (Velocity of the bus in both cases is the same)

• Zero
• 1.5x
• 2x
• 2.5x