GK
PHYSICS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Which of the following situations show non-zero work done? I. Pulling a trolley along a horizontal floor II. Pushing the ceiling of SM Supermalls III. Stamping your feet on the ground IV. Carrying the laundry basket to the laundry area
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I only
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III only
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I and II only
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III and IV only
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Explanation:
Detailed explanation-1: -In third case displacement is non-zero and force is also non-zero. So work done is non-zero.
Detailed explanation-2: -If the object is not moved even an inch by the applied force, then no work is said to be done. Some more examples of no work done are given below: You sit on a chair for hours. If a block moves on a smooth horizontal surface, no work is done.
Detailed explanation-3: -On smooth floor frictional force is zero, therefore work done is zero.
Detailed explanation-4: -When we stand holding a bag in our hands and do not move it, as there is no displacement, thus the work done is zero. If you push a wall and it doesn’t move, work is not done as there is no displacement.
There is 1 question to complete.