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प्रश्न
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.
उत्तर
- Yes, there can be displacement in an object in the absence of force. If the object is moving at a uniform speed, then no external force acts on that object, but there is displacement in the object.
- When an object is released in a free state from an inclined plane, it comes down due to the force of gravity, but on reaching the earth's surface, no force acts on it in the horizontal direction.
- That object moves at a uniform speed in the horizontal direction, and displacement keeps occurring in it.
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संबंधित प्रश्न
Write an expression for the work done when a force is acting on an object in the direction of its displacement.
Define 1 J of work.
Look at the activity below. Reason out whether or not work is done in the light of your understanding of the term ‘work’.
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Define the term 'work'. Write the formula for the work done on a body when a force acts on the body in the direction of its displacement. Give the meaning of each symbol which occurs in the formula.
Is work done a scalar or a vector physical quantity?
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.
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