A 5.30 g bullet moving at 963 m/s strikes a 610 g wooden block at rest on a frictionless surface. The bullet emerges, traveling in the same direction with its speed reduced to 426 m/s. (a) What is the resulting speed of the block? (b) What is the speed of the bullet-block center of mass?

a) = 4.67m/s

b) V = 8.29 m/s

Explanation:

Givens:

The bullet is 5.30g moving at 963m/s and its speed reduced to 426m/s. The wooden block is 610g.

a) From conservation of linear momentum

Pi = Pf

where are the mass and the initial velocity of the bullet, and are the mass and the initial velocity of the wooden block, and and are the final velocities of the wooden block and the bullet

The wooden block is initial at rest this yields

By solving for adn substitute the givens

=

=

= 4.67m/s

b) The center of mass speed is defined as

substituting:

V = 8.29 m/s

15.3 cos 65 degrees trig

when two balls of the different masses are dropped from equal height, they reach the ground at the same time .this is because they experience the same acceleration.

the acceleration is independent of mass.

thus when they are dropped they will always maintain the same velocity and travel the same distance (neglect air resistance of course) at the same time.