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प्रश्न
State the S.I. unit of energy.
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उत्तर
S.I. unit of energy Joule (J).
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संबंधित प्रश्न
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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A body of mass 5 kg falls from a height of 10 m to 4 m. Calculate:
The loss in potential energy of the body,
What do you mean by degradation of energy?
Define 1 joule of work.
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What is the work done against gravity when a body is moved horizontally along a frictionless surface?
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(a) by the force applied by the boy?
(b) by the gravitational force of earth?
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Name the physical quantity whose SI unit is Nm.
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The point O lies in the same plane. Given, P = Q = R = 10N
(i) Which force has the least moment about O? Give a reason.
(ii)Which force has the greatest moment about O? Give a reason.
Name the type of energy possessed by a
(i) stretched catapult (ii) hot iron
(iii) wound up clock
Fill in the boxe to show the corresponding energy transformation.
A girl of mass 40 kg runs a height of 80 stairs, each 25 cm high with a load of 20 kg on her head in 25 sec. If g is 10 m/s2, find:
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(ii) Work done by her.
(iii) Useful work done by her.
(iv) Her power in watt.
What is power? How do you differentiate kilowatt from kilowatt-hour? The Jog Falls in Karnataka state are nearly 20 m high. 2000 tonnes of waterfalls from it in a minute. Calculate the equivalent power if all this energy can be utilized? (g = 10 m s–2)
