Question

A 0.5 kg ball is dropped from the height of 10 m above the sidewalk. Calculate the speed of the ball just before it strikes the sidewalk?

• A. 5 m/s
• B. 10 m/s
• C. 14 m/s
• D. 28 m/s
• E. 200 m/s

Answer 1

The correct option is C 14 m/s

Given : $u=0$ m/s $m=0.5kg$ $S=10$ m $a=g=9.8m/s^2$

Using $v^2-u^2=2aS$

$\therefore$ $v^2-0=2\times 9.8\times 10$ $⟹v=\sqrt{196}=14$ m/s