Question

A small body is dropped from a rising balloon. A person $\text{A}$ stands on the ground, while another person $\text{B}$ is on the balloon. Choose the correct statement, immediately after the body is released.

• A. $\text{A}$ and $\text{B}$, both feel that the body is coming (going) down.
• B. $\text{A}$ and $\text{B}$, both feel that the body is going up.
• C. $\text{A}$ feels that the body is coming down, while $\text{B}$ feels that the body is going up.
• D. $\text{A}$ feels that the body is going up, while $\text{B}$ feels that the body is stationary.

Answer 1

The correct option is D $\text{A}$ feels that the body is going up, while $\text{B}$ feels that the body is stationary.

When the body is dropped from the balloon, it also acquires the upward velocity of the balloon. So w.r.t. a person on the ground, the ball appears to be going up. But a person in the balloon is also going up w.r.t him the velocity of the body will be zero and will thus see the body to be stationary.

$$\begin{array}{c}\text{Why this question?}\\ \text{When a body is gently released from}\\ \text{a balloon, it also acquires the velocity}\\ \text{of the balloon at that instant. The relative}\\ \text{velocity between the body and balloon}\\ \text{is zero at the instant when it is gently}\\ \text{dropped from the balloon.}\end{array}$$