Chapter-6: Work, Energy And Power |
1. The commercial unit of energy is-
- Watt
- Joule
- Kilowatt-hour
- None of these
2. The product of force and displacement is called –
- Energy
- Momentum
- Power
- Work
3. Work will be said not to be done if the force and displacement are –
- parallel
- acting in the opposite direction
- perpendicular
- None of these
4. Energy is-
- the capacity for doing work
- rate of doing work
- change of work
- None of these
5. Potential energy of an object of mass ‘m’ at a height ‘h’ is –
- 1/2mv²
- m²gh
- mgh
- mg
6. The expression of kinetic energy is –
- 1/2mv²
- m²gh
- mgh
- mg
7. Out of the following, which is not the unit of energy –
- Joule
- Calorie
- Kilo-Watt
- Electron-Volt
8. Joule is a unit of –
- Work and Power
- Power and Energy
- Force
- Work and Energy.
9. Area under the Force-Displacement curve represents –
- Velocity
- Impulse
- Acceleration
- Work done
10. The momentum of a body increased by 25%, then kinetic energy is increased by about –
- 25 %
- 56 %
- 5 %
- 38 %
11. The rate of doing work is called –
- energy
- force
- power
- pressure
12. What will be the kinetic energy of a substance when its velocity is doubled?
- Double
- Four times
- Half
- One-fourth
13. What will be the kinetic energy of a body when its velocity is halved?
- Double
- Four times
- Half
- One-fourth
14. Watt is the unit of the following –
- Work
- Power
- Energy
- None of these
15. If the velocity of a body becomes double then its kinetic energy becomes –
- Double
- Four times
- Half
- One-fourth