Question

What is the velocity of a body of a mass 100 g having k.e of 20 j?

Answer 1

Kinetic energy = mass x velocity squared, all divided by 2.
Remember to convert grams to kilograms first.
20 = 0.100 x velocity squared, all divided by 2.
40 = 0.100 x velocity squared
400 = velocity squared
Hence velocity is 20 m/s.
Hope it helps!