Final answer: How fast does the block of wood move after being hit?

[chibichibi7554]

I am not sure if I am doing this question right.

A 10g bullet, traveling at 400 m/s hits a block of wood & emerges going at 350 m/s. How fast goes the block of wood move after being hit?

Is this the right way to solve it?:

mv of the bullet + mv of the block = mv' of the bullet + mv' of the block
(.01)(400)+0=(.01)(350)+(2)v
v=.25

 

[berkeman]

You left the mass of the block out of your problem statement but included it in the work as 2kg (right?). Other than that it looks like a correct application of the conservation of linear momentum. Oh, and be sure to include units on the answer -- many folks (including me) will mark you down for leaving them off.