# Muzzle Velocity by Analyzing Ballistic Pendulum

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1. Dec 15, 2016

### ujellytek

1. The problem statement, all variables and given/known data
Finding the equation for the muzzle velocity by using conservation of energy.

2. The attempt at a solution

Ek+Eg=Ek2+Eg2
Well I'm 100% sure the kinetic energy of the ball is transferred into the catcher. The displacement is 1.9cm which is 0.019m. Mb=0.0077Kg (mass of ball) Mc=0.085Kg (mass of catcher)

Here is my work: .5Mbv^2=Mc*g*h <- this is supposed to be the total mass because the Mc and Mb become one, right? (btw that's the method my classmates used)
My method: .5Mbv^2=(Mc+Mb)*g*h
eventually v=sqrt( (2*g*h*(Mc+Mb))/Mb )

3. Relevant questions:

Is the proper equation for the muzzle velocity? v=sqrt((2*g*h*(Mc+Mb))/Mb)

I went to check this online, and I found out that the equation is supposedly supposed to be
v=(1+Mc/Mb)*sqrt(2*g*h)

2. Dec 15, 2016

### Staff: Mentor

Your problem statement is rather spare. You should describe the setup and define the variables you'll be using.

You might want to rethink that. What type of collision is involved? What's conserved? What's not conserved?

3. Dec 15, 2016

### TomHart

Also, you may just want to double check that all of the values are correct.