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संबंधित प्रश्न
State two conditions when no work is done by a force.
A coolie is moving on a road with a luggage on his head. Does he perform work against the force of gravity? Give reason for your answer.
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.
A box of weight 150 kgf has gravitational potential energy stored in it equal to 14700 J. Find the height of the box above the ground. (Take g = 9.8 N kg-1)
A boy throws a rubber ball vertically upwards. What type of work, positive or negative, is done : by the force applied by the boy?
(a) by the force applied by the boy?
(b) by the gravitational force of earth?
What happens to the work done when the dispacement of body is at right angles to the direction of force acting on it? Explain your answer.
A boy tries to push a truck parked on the roadside. The truck does not move at all. Another boy pushes a bicycle. The bicycle moves through a certain distance. In which case was the work done more : on the trick or on the bicycle? Give a reason to support your answer.
Determine the amount of work done when an object is displaced at an angle of 30° with respect to the direction of the applied force.
A boy of mass m climbs up a staircase of vertical height h.
- What is the work done by the boy against the force of gravity?
- What would have been the work done if he uses a lift in climbing the same vertical height?
If an electric bulb of 100 watt is lighted for 2 hours, how much electric energy would be consumed?
Fill in the boxe to show the corresponding energy transformation.
Give an example
Electrical energy changes to heat energy.
What do you understand by the term energy? Is energy a scalar or vector? How is the energy possessed by a body measured?
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).
Who is the odd one out?
