Question

A coin tossed in the air with a velocity of 30 m/s reaches back to the thrower in 0.4 sec. What is the highest point reached by the coin?

• A. 5.80 m
• B. 12 m
• C. 20 m
• D. 18.5 m

Answer 1

The correct option is A 5.80 m

Given:
Initial velocity = $30m/s$
Final velocity = $0m/s$
Time = $0.4sec$. (to return back)
$\therefore$ time for upward motion $=\frac{0.4}{2}=0.2$
Acceleration due to gravity = $-9.8m/s$${}^2$
By using the formula,$s=ut+\frac{1}{2}g{t}^2$
$s=30\times 0.2+\frac{1}{2}\times -9.8\times (0.2{)}^2$
$s=6-0.196$
$s=5.80m$
The maximum height reached by the coin is $5.80m$