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प्रश्न
Does the earth move around the sun with a uniform velocity?
उत्तर
No, the earth moves round the sun with a variable velocity. Since the direction of motion changes at each and every point the velocity becomes variable.
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संबंधित प्रश्न
A force of 7 N acts on an object. The displacement is, say 8 m, in the direction of the force (see the given figure). Let us take it that the force acts on the object through the displacement. What is the work done in this case?
Can there be displacement of an object in the absence of any force acting on it? Think. Discuss this question with your friends and teacher.
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Define the term 'work'. Write the formula for the work done on a body when a force acts on the body in the direction of its displacement. Give the meaning of each symbol which occurs in the formula.
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Name the physical quantity associated with the 'rate of doing work'.
If an electric bulb of 100 watt is lighted for 2 hours, how much electric energy would be consumed?
Give an example
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A coolie, with a load of 30 kg on his head, walks on the platform. If he walks a distance of 60 m, what is the work done by him?
Name the material commonly used for the manufacturing of solar cells.
One labourer carried four pans of road metal through a distance of 100 metres. If he carries two pans of road metal through a 200 metre distance ______ work will be done.
A is a push or a pull ______.
Work done by this force at any instant is ______.
