GK
PHYSICS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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True
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False
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Either A or B
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None of the above
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Detailed explanation-1: -Work is the amount of energy necessary to move an object. The further you move it, the more work is required. Work is measured in Newtons.
Detailed explanation-2: -Contrary to popular belief, machines do not increase the amount of work that is done. They just change how the work is done. Machines make work easier by increasing the amount of force that is applied, increasing the distance over which the force is applied, or changing the direction in which the force is applied.
Detailed explanation-3: -The work W done on an object by a constant force is defined as W = F·d. It is equal to the magnitude of the force, multiplied by the distance the object moves in the direction of the force. In the example above F = mg = (20 kg)(9.8 m/s2) = 196 N, W = (196 N)(1.5 m) = 294 Nm.
Detailed explanation-4: -What is true about all real machines? Work output < Work input. An “ideal friction-less” machine is imaginary.