Q127 / 180 · KCET 2017 · Physics
Two balls are thrown simultaneously in air. The acceleration of the centre of mass of the two
balls when in air,
balls when in air,
- Adepends on the masses of the two balls
- Bdepends on the speeds of the two balls
- Correct answerCis equal to \( \mathrm{g} \) (Acceleration due to gravity)
- Ddepends on the direction of motion of the two balls.
Solution
\[
\begin{array}{l}
\text { Acceleration of centre of mass }=\frac{m_{1}(-g)+m_{2}(-g)}{m_{1}+m_{2}} \\
=-g \frac{\left(m_{1}+m_{2}\right)}{\left(m_{1}+m_{2}\right)}=-g
\end{array}
\]
Therefore, acceleration of centre of mass of two balls in air is equal to \( \mathrm{g} \), that is, acceleration due to gravity
Therefore, acceleration of centre of mass of two balls in air is equal to \( \mathrm{g} \), that is, acceleration due to gravity
Hence, the correct answer is option: 'C'.