Weight is the force of gravity acting on an object's mass (W = mg). Apparent weight is the normal force exerted by the supporting surface on the object. When the lift cable breaks, the lift and everything inside it are in free fall, accelerating downwards at the acceleration due to gravity (g). In a state of free fall, there is no supporting force counteracting gravity. Therefore, the apparent weight of the man (the force exerted by the lift floor on him) becomes zero. This is the sensation of weightlessness. His actual weight (mass g) remains the same, but his apparent weight is zero.
A man weighing 70 kg is coming down in a lift. If the cable of the lift breaks suddenly, the weight of the man would become
Asked in UPSC NDA 1 2016 · Topic: Motion under Gravity (Equations of motion for objects under free fall)
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