Question

Two marbles, one twice as heavy as the other, are dropped to the ground from the roof of a building. Just before hitting the ground, the heavier marble has [...] as the lighter one. A. as much kinetic energy B. twice as much kinetic energy C. half as much kinetic energy D. four times as much kinetic

Answer 1

Answer:

 B. twice as much kinetic energy

Explanation:

Lets take the mass of the first marble =2 m

the mass of the second marble = m

We know that velocity of particle does not depends on their mass that is the velocity of both mass will be same after dropping from the roof.

We know that kinetic energy of a mass is given as

$KE=\dfrac{1}{2}Mv^2$

Kinetic energy for heavier mass

$KE=\dfrac{1}{2}\times 2m\times V^2$

Kinetic energy for light mass

$KE'=\dfrac{1}{2}\times m\times V^2$

KE=2 KE '

Form above two equation we can say that ,the kinetic energy for the heavier mass is twice the lighter mass.

Therefore the answer will be B.