Question

URGENT HELP NEEDED PLEASE!

A clay ball (mass = 0.25kg) has a rightward momentum of +1.75 kg∙m/s. A second clay ball (mass = 0.25 kg) has a leftward momentum of -1.75 kg∙m/s. The two collide, stick together, and come to a complete stop after the collision.
a) What was the total energy of the system before the collision?
b) What was the total energy of the system after the collision?

Answer 1

the total energy before collision is 12.25J

the total energy after collision is tranfered to sound and heat (by the friction between the two clay balls)

Step-by-step explanation:

first we should know the velocity of the 2 balls:

momentum=mass ×velocity

we have the momentum and the mass of the 2

so momentum ÷mass=velocity

clay ball 1 velocity=7 m/s & clay ball 2 velocity= -7 m/s

KE=1/2 mv²

1/2 ×0.25×7²=6.125J KE of ball 1

1/2 ×0.25×-7²=6.125J KE of ball 2

add them both we will have 12.25J which is before collision

this energy will then be tranfered to heat and sound as they stop after the collision(velocity =0m/s)