Question

A 2.45 g table tennis ball has the KE of 31.5 J. At what velocity is the tennis ball traveling?

Answer 1

KE =

`(1)/(2) mv {}^(2)`
Convert g in kg
Find v:
2KE = mv^2
v=√2KE/m
v=√2*31.5/0.00245
v=160 m/s

Answer 2

160.35 m/s

Step-by-step explanation:

Kinetic energy of a body depends on the mass (m) of the body and the speed (v) with it is moving. It is the energy possessed by body due to virtue of its motion.

K.E. = 0.5 m v²

It is given that, m = 2.45 g = 2.45 ×10⁻³ kg

K.E. = 31.5 J

`v = \sqrt{(2K.E.)/(m)} = √(2* 31.5){2.45 * 10^(-3)}=160.35 m/s`

Thus, the tennis ball is moving with the velocity of 160.35 m/s.