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प्रश्न
Select the correct alternatives
The correct statement is
पर्याय
Both work and energy have the same units
Potential energy of a body is due to its motion
Kinetic energy of a body is due to its position or state
Kinetic energy can change into potential energy, but potential energy cannot change into kinetic energy.
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उत्तर
Both work and energy have the same units
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संबंधित प्रश्न
Write true or false of the following statement.
One form of energy cannot be converted into another form.
Fill in the blank
Cooking gas converts _______ energy into heat energy.
Match the following:
| Column A | Column B |
| (a) Needle | (1) class II lever |
| (b) Doorknob | (2) inclined plane |
| (c) Ramp | (3) Class I lever |
| (d) Lemon crusher | (4) Wheel and axle |
| (e) Seesaw | (5) wedge |
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- Take two aluminium channels of different lengths.
- Place the lower ends of the channels on the floor and hold their upper ends at the same height.
- Now take two balls of the same size and weight and release them from the top end of the channels. They will roll down and cover the same distance.
- At the moment of releasing the balls, which energy do the balls have?
- As the balls roll down which energy is converted into which other form of energy?
- Why do the balls cover the same distance on rolling down?
Note: The question is wrong. It should be "Why do the balls cover the same distance after rolling down"? - What is the form of the eventual total energy of the balls?
- Which law related to energy does the above activity demonstrate? Explain.
If the energy of a ball falling from a height of 10 metres is reduced by 40%, how high will it rebound?
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There is a car. Its tank is full of fuel but it does not move. Why is that?
