Question

A moving body of 30kg has 60 J of KE (Kinetic Energy) . Calculate the speed.

Answer 1

Answer:

1/2mv2=60

mv2=120

30×v2=120

v2=4

v=2m/s

Answer 2

Mass of the body = 30 kg

Kinetic Energy = 60 J

Speed = ?

Using formula of Kinetic Energy,

$K.E = \dfrac{1}{2} \times m \times v^2\\\\60 = \dfrac{1}{2} \times 30 \times v^2\\\\v^2 = \dfrac{60 \times 2}{30}\\\\v =\sqrt{2\times 2} \\\\v = 2 \ ms^{-1}$

Hence, velocity or speed of body is 2 m/s.