Share
Explore BrainMass

Work-Energy Concepts

A 5.0g bullet if fired horizontally into a 2.0kg wooden block resting on a horizontal surface. The coefficient of kinetic friction between block and surface is 0.20. The bullet remains imbedded in the block, which slides 0.105m along the surface. What was the initial speed of the bullet? (My problem with this is that there is no acceleration given, such as gravity serves in a ballistic pendulum problem- how do you do this without acceleration and/or how to you calculate it?)

Solution Preview

Let v be the initial speed of the bullet
Then, Kinetic Energy of the bullet = ½mv^2 = ½*0.005v^2 = 0.0025v^2 J
Since the block was at rest initially on a ...

$2.19