FrictionHard
Question
A man of mass 60 kg records his wt. on a weighing machine placed inside a lift. The ratio of wts. of man recorded when lift ascending up with a uniform speed of 2 m/s to when it is descending down with a uniform speed of 4 m/s will be
Options
A.0.5
B.1
C.2
D.none of these
Solution
Net force of reaction act on a body in a lift when it is accelerating. If lift moves up or down with uniform speed then acceleration a = 0,
∴   weight of man =mg is same in ascending hence ratio = 1.
∴   weight of man =mg is same in ascending hence ratio = 1.
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