Question

1. A person has 1000 J of kinetic energy. What is their velocity if they have a mass of 100kg?

Answer 1

We can find the velocity of the person from the definition of the kinetic energy:

$$KE=\dfrac{1}{2}mv^2,$$ $$v=\sqrt{\dfrac{2KE}{m}},$$ $$v=\sqrt{\dfrac{2\cdot1000\ J}{100\ kg}}=4.47\ \dfrac{m}{s}.$$