Answer:
20 J
Explanation:
Kinetic energy is given as half of the product of mass and the square of velocity of an object:
KE = [tex]\frac{1}{2}mv^2[/tex]
where m = mass = 40 kg
v = velocity = 1 m/s
Hence, Mary's kinetic energy is:
KE = [tex]\frac{1}{2} * 40 * 1^2[/tex]
KE = 20 * 1 = 20 J
She has a kinetic energy of 20 J.
