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प्रश्न
In the following case write yes, if the work is being done and no if no work is being done.
A coolie standing with a heavy load on his head
State whether work is done or not, by writing yes or no, in the following case:
A coolie stands with a box on his head for 15 min.
विकल्प
Yes
No
उत्तर
No.
APPEARS IN
संबंधित प्रश्न
Define 1 joule of energy.
How is work related to energy?
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 machine raises a load of 750 N through a height of 16 m in 5 s. calculate:
- energy spent by machine,
- power at which the machine works.
A boy of weight 40 kgf climbs up the 15 steps, each 15 cm high in 10 s and a girl of weight 20 kgf does the same in 5 s. Compare:
- the work done, and
- the power developed by them. Take g = 10 N kg-1.
The work done on an object does not depend on ______.
Its moment of a force scalar or a vector quantity?
Give two examples of couple action in our daily life.
Can every force produce work?
An object is dropped from a height H. when is its
(i) P.E. maximum,
(ii) K.E. maximum,
(iii) P.E. = K.E.?
What do you understand by 'potential energy' and 'Kinetic energy'? Give three examples of each to illustrate your answer.
Name two places in India where electricity is generated from nuclear power plants.
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 ______.
