A man, of mass 60kg, is riding in a lift. The weights of the man, when the lift is acceleration upwards and downwards at `2ms^(-2)` are respectively.
(Taking `g=10ms^(-2)`)

Options

A. 720 N and 480N
B. 480N and 720N
C. 600N and 600N
D. None of these

Answer

A

Explanation

Here, `m=60kg. G=10ms^(-2), a-2 ms^(-2)`
When the lift is accelerating upwards with constant acceleration a, the weight of the man is `W=m(g+a)=60(10+2)=720N`
When the lift is accelerating downwards with same acceleration a, the weight of the man is
`W"=m(g-a)=60(10-2)=480N`