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प्रश्न
उत्तर १
The law of conservation of energy states that energy cannot be created or destroyed; the sum total of energy in a closed system remains unchanged. Energy only changes from one form to another.
उत्तर २
According to the law of conservation of mechanical energy, the sum of kinetic energy and potential energy always remains constant.
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संबंधित प्रश्न
A stone of mass m is rotated in a circular path with a uniform speed by tying a strong string with the help of your hand. Answer the following questions
1) Is the stone moving with a uniform or variable speed?
2) Is the stone moving with a uniform acceleration? In which direction does the acceleration act?
3) What kind of force acts on the hand and state its direction?
How is work done by a force measured when the force is in the direction of displacement?
How is the unit horsepower related to the S.I. unit of power?
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An engine does 54,000 J of work by exerting a force of 6000 N on it. What is the displacement in the direction of the force?
State and define the unit of force in the S.I. system.
Define 1 kgf., How is it related to the S.I. unit of force?
The world record for weight lifting was held by Sergei Didyk of the USSR. He lifted 261 kg to a height of 2.3 m in 4s; find:
(a) Weight lifted by him
(b) Work done by him
(c) Power developed by him. (g = 10m/s2)
State the C.G.S. unit of work. How it is related to its S.I. unit?
A man raises a box of mass 50 kg to a height of 2 m in 20 s, while another man raises the same box to the same height in 50 s. Compare:
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