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प्रश्न
Work done by a force is equal to the product of ....... and ....
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उत्तर
Applied force, displacement in the direction of the applied force.
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संबंधित प्रश्न
When does a force do work?
A body is moved in a direction opposite to the direction of force acting on it. State whether the work is done by the force or work is done against the force
One horse power is equal to ______.
kWh is the unit of ______.
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"]`
It takes 20 s for a person A of mass 50 kg to climb up the stairs, while another person B of same mass does the same in 15 s. Compare the power developed by the persons A and B.
A man raises a box of mass 50 kg to a height of 2 m in 20s, while another man raises the same box to the same height in 50s. Calculated:
- the work done, and
- the power developed by each man. Take g = 10 N kg-1.
A boy takes 3 minutes to lift a 20 litre water bucket from a 20 m deep well, while his father does it in 2 minutes. Compare:
- the work, and
- power developed by them.
What do you understand by work? Is work a scalar or a vector quantity?
In the following case write yes, if the work is being done and no if no work is being done.
A man moving on the rough ground.
