Available Answers

1. 1.

   Write true or false for each statement. Rewrite the false statement correctly.

   1. A car and a truck travel with same velocity. The car has more kinetic energy.
   2. A person climbing the stairs of a building is doing work.
   3. A man pushing a wall is doing work.
   4. A strong wind turns the blades of a windmill.
   5. A stone thrown with a high speed has potential energy.
   6. A kerosene stove converts the chemical energy into light energy.
   7. The mechanical energy of a body is the difference of its K.E. and PE.
   8. A generator converts mechanical energy into electrical energy.
   9. The amount of energy possessed by a body is equal to the amount of work it can do when that energy is released.
2. 2.

   Fill in the blanks:

   1. The work done by the moon in revolving around the earth is _________________.
   2. A bent bow possesses _________________ energy.
   3. The total amount of energy possessed by universe _________________.
   4. A microphone converts energy into _________________ energy.
   5. If the mass of a moving object is doubled, its kinetic energy _________________.
   6. The work done by the earth in revolving round the sun is _________________.
   7. _________________ is consumed whenever work is done.
3. 3.

   Tick the appropriate answer :

   1. The S.I. unit of work is
      1. newton
      2. erg
      3. Joule
      4. meter
   2. If you push a wall with a force 50N, the work you do is
      1. 500 J
      2. 5000 J
      3. 50 J
      4. zero
   3. The capacity to do work by a body in a unit time is called its
      1. power
      2. muscular energy
      3. energy
      4. None of the above
   4. If the velocity of a body is decreased,
      1. kinetic energy remains same
      2. kinetic energy increases
      3. kinetic energy decreases
      4. none of the above
   5. In a compressed spring, energy is in the form of
      1. potential energy
      2. kinetic energy
      3. chemical energy
      4. sound energy
   6. The energy possessed by a body due to its motion is called
      1. potential energy
      2. kinetic energy
      3. muscular energy
      4. none of the above
4. 4.

   Match the following:

   A cell An electric bulb A mixer grinder A loudspeaker A fire cracker

   Electrical to sound Electrical to mechanical Electrical to heat and light Chemical to heat, light and sound Chemical to Electrical

5. 5.

   Define potential energy. What are the factors on which on which depend the amount of potential energy?

6. 6.

   Define kinetic energy. What are the factors on which depends the amount of kinetic energy?