Question

A juggler is juggling $7$ balls simultaneously. If the time gap to pass ball from one hand to the other is $2$ second then find the maximum height attained by each ball.

• A. $100\text{m}$
• B. $120\text{m}$
• C. $180\text{m}$
• D. $200\text{m}$

Answer 1

The correct option is C $180\text{m}$

$\begin{array}{cc}t=0\text{second}\Rightarrow 1^{st}\text{Ball}& \\ t=2\text{second}\Rightarrow 2^{nd}\text{Ball}& \\ t=4\text{second}\Rightarrow 3^{rd}\text{Ball}& \\ t=6\text{second}\Rightarrow 4^{th}\text{Ball}& \\ t=8\text{second}\Rightarrow 5^{th}\text{Ball}& \\ t=10\text{second}\Rightarrow 6^{th}\text{Ball}& \\ t=12\text{second}\Rightarrow 7^{th}\text{Ball}& \end{array}$

$\text{As we know that, time of flight is given as}\Rightarrow T=\frac{2u}{g}\Rightarrow 12=\frac{2\times u}{10}\Rightarrow u=60m/s{H}_{max}=\frac{u^2}{2g}=\frac{3600}{20}=180\text{m}$