A body stands on a weighing machine inside a lift. When the lift is going down wit acceleration `g//4`, the machine shows a reading 30 kg. When the lift goes upwards with acceleration `g//4`, the reading would be

Options

A. `18 kg `
B. `37.5 kg `
C. `50 kg `
D. `67.5 kg `

Answer

C

Explanation

The reading would change from
`(g-(g)/(4)) " to" (g + (g)/( 4)) `i.e.,from` (3g)/(4) " to " ( 5g)/(4)`
The factor is `(5)/(3) " " therefore ` New reading `=(5)/(3) xx 30 kg =50 kg`