- #1

- 365

- 0

## Homework Statement

A bullet with a mass of 7.00 g is fired horizontally with a speed of 420 m/s, into a wooden block with mass of 0.820 kg, initially at rest on a level surface. The bullet passes through the block and emerges with its speed reduced to 130 m/s. The block slides a distance of 47.0 cm along the surface from its initial position.

**What is the coefficient of kinetic friction between block and surface?**

## Homework Equations

vf

^{2}=vi

^{2}+2ad

F=ma

u

_{k}= f

_{k}/n

## The Attempt at a Solution

I found the acceleration of the bullet

130

^{2}=420

^{2}+2a(.47)

a= -169680.8

i then thought i could find the force and then divide that by the normal force to get u

_{k}but my number was very large (141) :(

Can anyone help me on this one please.

Thank you :)