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DDarthVader
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Homework Statement
Hello! I'm trying to solve this exercise:
A bullet with initial velocity v and mass m pass through a block of mass M in a pendulum of length L and leave the block with velocity v/2. Which value of v will make the pendulum describe a circumference?
As you can see, English is not my native language.
Homework Equations
The Attempt at a Solution
I think this is a inelastic collision so this is what I did.
[itex]K_{1i}+K_{2i}=K_{1f}+K_{2f}[/itex] but the pendulum has velocity 0 when the bullet hit it so [itex]K_{1i}+0=K_{1f}+K_{2f}[/itex].
Using the information above. [itex]\frac{mv^2}{2}=\frac{mv^2}{8}+\frac{Mv^2}{2}[/itex]. I did this because the kinetic energy is conserved so I think I can use this to get to the mechanical energy which will give me [itex]Mg2L=K[/itex]. I think this is the way but honestly I don't know how to get the K to make it equal to the potential energy.