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प्रश्न
A boy does work when he pushes against a brick wall. (yes/no).
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उत्तर
Yes
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संबंधित प्रश्न
Derive a relationship between S.I. and C.C.S. unit of work
A boy of mass 40 kg climbs up the stairs and reaches the roof at a height 8 m in 5 s. Calculate:
- the force of gravity acting on the boy,
- the work done by him against the force of gravity,
- the power spent by boy. (Take g = 10 m s-2)
A force of 50 N acts on a body and moves it a distance of 4 m on horizontal surface. Calculate the work done if the direction of force is at an angle of 60° to the horizontal surface.
A boy tries to push a truck parked on the roadside. The truck does not move at all. Another boy pushes a bicycle. The bicycle moves through a certain distance. In which case was the work done more : on the trick or on the bicycle? Give a reason to support your answer.
Give two examples of couple action in our daily life.
A man carrying a suitcase in his hand is walking horizontally. What is the work done against gravity?
Define 'joule'.
What do you understand by the term energy? Is energy a scalar or vector? How is the energy possessed by a body measured?
Look at the activity below. Reason out whether or not work is done in the light of your understanding of the term ‘work’.
Food grains are getting dried in the sun.
State whether work is done or not, by writing yes or no, in the following case:
A boy climbs up 20 stairs.
