Question

Mary has a mass of 40 kg and sprints at 1 m/s. How much kinetic energy does she have?

Answer 1

Answer:

20 J

Explanation:

Kinetic energy is given as half of the product of mass and the square of velocity of an object:

KE = $\frac{1}{2}mv^2$

where m = mass = 40 kg

v = velocity = 1 m/s

Hence, Mary's kinetic energy is:

KE = $\frac{1}{2} * 40 * 1^2$

KE = 20 * 1 = 20 J

She has a kinetic energy of 20 J.