A 2.3 kg object moving at 7.3 m/s collides inelastically with a 4.0 kg object which is initially at rest.What percentage of the initial kinetic energy of the system is lost during the collision?
A)63 %
B)74 %
C)57 %
D)52 %

Question

Quizplus · Accepted Answer

First, we need to calculate the velocity of the system after the collision using conservation of momentum:

(2.3 kg)(7.3 m/s) + (4.0 kg)(0 m/s) = (2.3 kg + 4.0 kg)(vf)

vf = 3.18 m/s

Next, we can calculate the initial kinetic energy of the system:

KEi = (1/2)(2.3 kg)(7.3 m/s)^2 = 77.4 J

Now, we can calculate the final kinetic energy of the system:

KEf = (1/2)(6.3 kg)(3.18 m/s)^2 = 30.8 J

The percentage of kinetic energy lost during the collision is:

(KEi - KEf)/KEi x 100% = (77.4 J - 30.8 J)/77.4 J x 100% = 60.4%

Therefore, the closest choice is A)63%.

A 23 Kg Object Moving at 7