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HELP how to know direction of mvmnt and acc from a weighing scale in a lift PLS

A person weighing 100 N stands on some bathroom scales in a lift. If the scales show areading of 110 N, which answer could describe the motion of the lift? The answer is Moving downwards and decelerating...why? I thought it would be downwards and accelerating although not such choice
Original post by sarah99630
Person weighing 100 N stands on scales in a lift. If the scales show a reading of 110 N, which answer could describe the motion of the lift? Ans: downwards & decelerating, why?

If lift & contents decelerate, there's upward force on the lift, but also on the person; more reaction by the scales. More force on scales by N3, higher reading. Think of a lift grinding to halt; feel larger force from below as floor pushes into you, the floor feels it too.
(edited 5 years ago)

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