Advertisements
Advertisements
प्रश्न
A water pump raises 50 kg of water through a height of 25 m in 5s. Calculate the power supplied by the pump (Take: g = 10 N kg−1).
उत्तर
Given m = 50 kg, g = 10N kg−1, d = 25 m, t = 5s.
Force of gravity F = mg
= 50 × 10
= 500 N
Work done W = F × d
= 500 × 25
= 12,500 J
Power P =`"W"/"t" = (12,500)/5=2500"W".`
APPEARS IN
संबंधित प्रश्न
Write an expression for the work done when a force is acting on an object in the direction of its displacement.
A coolie does no work against the force of gravity while carrying a luggage on a road.
State two conditions when no work is done by a force.
State the S.I. unit of work and define it.
A body, when acted upon by a force of 10 kgf, moves to a distance 0.5 m in the direction of force. Find the work done by the force. Take 1 kgf = 10 N.
A girl is carrying a school bag of 3 kg mass on her back and moves 200 m on a levelled road. If the value of g be 10 m/s2, the work done by the girl against the gravitational force will be :
The work done on an object does not depend on the :
A man carrying a suitcase in his hand is walking horizontally. What is the work done against gravity?
An object is dropped from a height H. when is its
(i) P.E. maximum,
(ii) K.E. maximum,
(iii) P.E. = K.E.?
Name the physical quantity associated with the 'rate of doing work'.
A 100 W electric lamp emits energy in the form of light at the rate 10 J per second. What percentage of electric energy does the lamp transform into light energy?
Calculate the amount of work done by a child carrying a bag of 20 kg when he moves a distance of 40 m in
(a) Vertical direction, and
(b) Horizontal direction
How fast should a boy weighting 30 kg run so that his kinetic energy is 375 joule?
A girl of mass 50 kg runs up a flight of 40 steps in 20 seconds. If each step in 20 cm high, calculate the power developed by the girl. (g= 10 ms-2).
The weights of two bodies are 2.0 N and 2.0 kgf respectively what is the mass of each body?
