(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A 4.00-g bullet, travelling horizontally with a velocity of magnitude 400 m/s, is fired into

a wooden block with mass 0.800 kg, initially at rest on a level surface. The bullet passes

through the block and emerges with its speed reduced to 120 m/s. The block slides a

distance of 45.0 cm along the surface from its initial position.

(i) What is the coefficient of kinetic friction between block and surface?

(ii) What is the decrease in kinetic energy of the bullet?

(iii)What is the kinetic energy of the block at the instant after the bullet passes through it?

We have a physics exam coming up and they gave us a couple of practice questions with no answers. I solved these but im unsure if there correct can someone please take a look. thanks

i) 0.221996

ii) 291.2J

iii) 0.784J - i actually found this one while solving i) i used W=Fs i think you can use kinematics for acceleration and the use F=ma

2. Relevant equations

3. The attempt at a solution

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# Homework Help: Ballistics pendulum - sort of - COM

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