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प्रश्न
Name the physical quantity associated with the 'rate of doing work'.
उत्तर
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संबंधित प्रश्न
State two conditions when no work is done by a force.
Write the expression for work done by a force.
Express joule in terms of erg.
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 boy weighing 25 kgf climbs up from the first floor at height 3 m above the ground to the third floor at height 9m above the ground. What will be the increase in his gravitational potential energy? (Take g = 10 N kg -1)
A vessel containing 50 kg of water is placed at a height 15 m above the ground. Assuming the gravitational potential energy at ground to be zero, what will be the gravitational potential energy of water in the vessel? (g = 10 m s-2)
State the SI unit of work.
Give one example each in which a force does (a) positive work (b) negative work, and (c) zero work.
A person of mass 50 kg climbs a tower of height 72 metres. Calculate the work done. (g = 9.8 m s−2).
How much work is done when a force of 2 N moves a body through a distance of 10 cm in the direction of force?
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.
The velocity of a car increases from 54 km/hr to 72 km/hr. How much is the work done if the mass of the car is 1500 kg?
What do you mean by a kilo joule?
Fill in the boxe to show the corresponding energy transformation.
Give an example
Light energy changes to electrical energy.
A body of mass 0.5 kg travels on straight line path with velocity v = (3x2 + 4) m/s. The net work done by the force during its displacement from x = 0 tox = 2 m is ______.
