Question

when a ball is thrown vertically upward with a velocity 70 metre per second find maximum height and time to attain the height​

Answer 1

Answer:

By energy conservation

$\frac{1}{2} m {v}^{2} = mgh \\ \frac{1}{2} \times 70 \times 70 = 10 \times h \\ \\ h = 245m \\ by \: 1st \: eq \: of \: motion \\ v = u - gt \\ 0 = 70 - 10 \times t \\ t = 7sec$

hope the answer will help you

Answer 2

Explanation:

u(initial velocity) = 70 m/s

at highest point v(final velocity)=0

using v=u+at

0=70 - 9.8 * t

t=70/9.8= 7.14s (time to reach max height)

now using v ^2- u^2 = 2as

0 - (70)^2 = 2* 9.8 * s

s= 70×70/2*9.8

s= 250 m

hope it will help you ;)..