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संबंधित प्रश्न
Define 1 J of work.
Can there be displacement of an object in the absence of any force acting on it? Think. Discuss this question with your friends and teacher.
Power spent by a body depends on the time for which it does work.
A man lifts a mass of 20 kg to a height of 2.5 m. Assuming that the force of gravity on 1 kg mass is 10 N, find the work done by the man.
State the law of conservation of energy.
Write the formula for work done on a body when the body moves at an angle to the direction of force. Give the meaning of each symbol used.
The work done on an object does not depend on the :
What is the relationship between Nm and dyne cm?
Name the force acting away from the centre of circular path.
On what factors does the work done by a force depend?
Complete the following sentences:
Joule is the unit of .......
A block of mass 20 kg is pulled up a slope (fig.12) with a constant speed by applying a force of 500 N parallel to the slope. A and B are initial and final positions of the block.
(a) Calculate the work done by the force in moving the block from A and B.
(b) Calculate the potential energy gained by the block.
List any six forms of energy and write a short note on each of them.
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).
State the energy changes which take place when An electric bulb glows when it is connected to a source of electric current.
Explain, why submarines are able to dive underwater as well as a sail on the surface of the water?
What are the advantages and disadvantages of using solar cells for producing electricity?
An electric motor pump is 60% efficient and is rated 2.5 H.P. Calculate the maximum load it can lift through a height of 10m in 8 sec. (1 H.P. = 750 W).
