Question

Two balls $A$ and $B$ of the same size are dropped from the same point under gravity. If the air resistance acting on both the balls is same and the mass of $A$ is greater than the mass of $B$, then

• A. $\text{The ball}A\text{reaches earlier.}$
• B. $\text{The ball}B\text{reaches earlier.}$
• C. $\text{Both the balls reach the ground simultaneously.}$
• D. $\text{Cannot say, as the data is insufficient.}$

Answer 1

The correct option is A $\text{The ball}A\text{reaches earlier.}$

Let the air resistance force acting on the balls be $F$

From the figure acceleration of the ball is given by
$a=\frac{mg-F}{m}=g-\frac{F}{m}$
$\because m_A>m_B$
$\Rightarrow a_A>a_B$
Hence, ball $A$ will reach the ground earlier.