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संबंधित प्रश्न
When do we say that work is done?
Soni says that the acceleration in an object could be zero even when several forces are acting on it. Do you agree with her? Why?
The moon is revolving around the earth in a circular path. How much work is done by the moon?
A force of 30 N acts on a body and moves it through a distance of 5 m in the direction of force. Calculate the work done by the force.
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.
Express joule in terms of erg.
Name the forms of energy which a wound-up watch spring possesses.
State the energy transformation on the following:
Electricity is obtained from solar energy.
When is the work done by a force on a body : (a) positive, (b) negative, and (c) zero?
A max X goes to the top of a building by a vertical spiral staircase. Another man Y of the same mass goes to the top of the same building by a slanting ladder. Which of the two does more work against gravity and why?
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?
Name the force acting away from the centre of circular path.
What do you mean by a kilo joule?
A weight lifted a load of 200 kgf to a height of 2.5 m in 5 s. calculate: (i) the work done, and (ii) the power developed by him. Take g= 10 N kg-1.
Name the physical quantity whose MKS units are kgm2s-3.
State the energy changes which take place when A stone dropped from the top of a cliff reaches the ground after some time.
A girl of mass 40 kg runs a height of 80 stairs, each 25 cm high with a load of 20 kg on her head in 25 sec. If g is 10 m/s2, find:
(i) Gravitational force acting on the girl.
(ii) Work done by her.
(iii) Useful work done by her.
(iv) Her power in watt.
A ______ should act on an object.
