A bullet of mass m and velocity strikes and becomes imbedded in a wooden block of mass M, which is initially at rest on a frictionless surface. The ratio of the velocity of the system after collision to the initial velocity of the bullet is

Question

A bullet of mass m and velocity  strikes and becomes imbedded in a wooden block of mass M, which is initially at rest on a frictionless surface. The ratio of the velocity of the system after collision to the initial velocity of the bullet is

Quizplus · Accepted Answer

Conservation of momentum can be applied to the system:
m * 11eb1367_5154_c049_8021_773a2c96d1b2_TB7291_11 = (m + M) * (v)
where v is the velocity of the combined system after the collision.
Solving for v, we get: 
v = (m * 11eb1367_5154_c049_8021_773a2c96d1b2_TB7291_11) / (m + M)
The ratio of final velocity to initial velocity of the bullet is:
v / 11eb1367_5154_c049_8021_773a2c96d1b2_TB7291_11 = (m / (m + M))
This can be written as:
(m / m + M) / 1
Therefore, the answer is D, m/m + M).

A Bullet of Mass M and Velocity Strikes and Becomes