Question

A balloon with mass `m` is descending down with an acceleration a `(where altg)` . How much mass should be removed from it so that it starts moving up with an acceleration a?
A. `(2ma)/(g-a)`
B. `(ma)/(g+a)`
C. `(ma)/(g-a)`
D. `(2ma)/(g+a)`

Answer 1

Correct Answer - D

Let the mass removed be `m_(0)`

Adding (i) and (ii), we get
`m_(0)g=(2m-m_(0))a=2ma-m_(0)a`
`m_(0)(g+a)=2ma`
`m_(0)=(2ma)/(g+a)`