posted by Sara .
A rifle bullet with a mass of 16.5 g traveling toward the right at 285 m/s strikes a large bag of sand and penetrates it to a depth of 22.6 cm. Determine the magnitude and direction of the friction force (assumed constant) that acts on the bullet.
initial momentum = .0165 * 285
change of momentum = -.0165*285
average speed during stop = 285/2
time to stop = .226/average speed during stop
Force = change in momentum / time to stop