Calculating Bullet Velocity: Impact on Wooden Block with Given Parameters

[kubombelar]

Homework Statement

Hey guys here is my problem:
A bullet is fired horizontally into a wood block attached to a string,the bullet sticks in the block.Calculate the velocity of the bullet if the impact causes the block to swing 10cm above its initial level. Bullet=15g, Block=3kg,Height=10cm.

. Relevant equations]
Square root of 2gh (were g is acceleration due to gravity,h is height. j

 

[tiny-tim]

Welcome to PF!

Hi kubombelar! Welcome to PF!

Start by using energy to find the initial velocity of the block.

Then use conservation of momentum. ​

 

[kubombelar]

Hey thanks. using the formula i stated,i found 14.1ms and 1.4ms if i convert cm to m. Am i correct?

 

[tiny-tim]

Hi kubombelar!

(what figure are you using for g?)

… i found 14.1ms and 1.4ms if i convert cm to m.

That's a weird way of putting it.

They can't both be correct, can they?

So which is it?
​

(and what do you then get for the velocity of the bullet?)