Two Physics questions

[GunnerVIII]

Ok i have 2 questions - the first one is this:

A bullet of mass 0.01kg travelling at velocity v hits a block of wood suspended on a long string. The mass of the block is 1.00kg

 

(a) find the bullets velocity v (i've already done this using)

 

(b) to what height does the block rise after collision?

Im thinking that this is a projectile motion question

 

 

Here is the second question:

When u hammer a nail into a wall the nail exerts a force on the wall, and the wall exerts a force on the nail. How then does the nail penetrate the wall

 

Any help would be great!!!

[Giles]

Can you just work out the KE, and then ask how high the block would rise if it was all converted to GPE?

[JaKiri]

Originally posted by Giles

Can you just work out the KE, and then ask how high the block would rise if it was all converted to GPE?

 

Yes.

[GunnerVIII]

Yeah i tried something like that using mgh=1/2mv^2 - 1/2 mu^2 and it worked