Question

- A ball is thrown vertically upward. It has a
speed of 10 m/sec. When it has reached one
half of its maximum height. How high does the
ball rise ? Take g = 10 m/s
(A) 10 m
(B) 5 m
(C) 15 m
(D) 30 m.
​

Answer 1

For part AB

From 3rd equation of motion

${v}^{2} - {u}^{2} = 2gh$

0=u^2-2g (H/2)=u^2-gH

$0 = {u}^{2} - 2g( \frac{h}{2} ) \\ \\ = {u}^{2} - gh$

$h = \frac{ {u}^{2} }{g} \\ \\ = \frac{ {10}^{2} }{10} \\ \\ = 10$

THEREFORE THE ANSWER IS 10m