Question

A tennis ball is thrown from a 25 m tall building with a zero initial velocity. At the same moment, another ball is thrown from the ground vertically upward with an initial velocity of 17 m/s. At which height will the two balls meet?

Answer 1

The two balls meet in 1.47 sec.

Step-by-step explanation:

Given that,

Height = 25 m

Initial velocity of ball= 0

Initial velocity of another ball = 17 m/s

We need to calculate the ball

Using equation of motion

`s=ut+(1)/(2)gt^2+h`

Where, u = initial velocity

h = height

g = acceleration due to gravity

Put the value in the equation

For first ball

`s_(1)=0-(1)/(2)gt^2+25`....(I)

For second ball

`s_(2)=17t-(1)/(2)gt^2+0`....(II)

From equation (I) and (II)

`-(1)/(2)gt^2+25=17t-(1)/(2)gt^2+0`

`t=(25)/(17)`

`t=1.47\ sec`

Hence, The two balls meet in 1.47 sec.