Question

A ball is thrown up with a speed of 15 meter per second.how high will it go before it begins to fall ? (g= 9.8 metre per second square)​

Answer 1

Answer:

it will go 11.4 m high

Explanation:

Given,

A ball is thrown up with a speed(u) of 15 meter per second.

Acceleration due to gravity = - 9.8 m/s^2

To find: how high will it go before it begins to fall ?

Solution:

We can use third equation of motion,

i.e $v^2 - u^2 = 2gh$

here, v = 0 (as ball stops at max. height for sometime)

and, u = 15 m/s, g = - 9.8 m/s^2 (as we are moving upward)

Substituting the values,

$0^2 - (15)^2 = 2\times(-9.8)\times h\\\\225 = 19.6h\\\\h=\dfrac{225}{19.6}\\\\h=11.4 \ m$

Therefore, it will go 11.4 m high.