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संबंधित प्रश्न
A boy weighing 40 kgf climbs up a stair of 30 steps each 20 cm high in 4 minutes and a girl weighing 30 kgf does the same in 3 minutes. Compare:
- The work done by them.
- The power developed by them.
One horse power is equal to ______.
A body of mass m is moving with a uniform velocity u. A force is applied on the body due to which its velocity changes from u to v. How much work is being done by the force?
Work is a scalar quantity because it is a measure of transfer of energy without indicating any direction
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?
A pump is used to lift 600 kg of water from a depth of 75 m in 10s. Calculate:
- The work done by the pump,
- the power at which the pump works, and
- The power rating of the pump if its efficiency is 40%. (Take g = 10m s-2).
`["Hint" : "Efficiency" = "useful power"/"power input"]`
State the condition when the work done by the force is positive
For the following scenario, state whether the work done by gravity is positive, negative, or zero.
A person walks on a levelled road.
