Calculating Bullet Speed: Pendulum Physics Homework Problem Solution

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To calculate the speed of a bullet lodged in a log, the relationship between kinetic energy (KE) and potential energy (PE) is essential, specifically using the equation ½mV² = mgh. The horizontal displacement, weight of the log, and string length provide the necessary parameters for the calculation. The discussion highlights the importance of understanding pendulum physics to solve the problem effectively. A resource link is shared for further assistance with pendulum-related calculations. Ultimately, the problem can be solved by applying the correct energy principles.
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Homework Statement


I have to calculate the speed of a bullet, based on the amount of displacement created when the bullet becomes lodged in the log.
I have the horizontal displacement, the weight of the log, and the length of the string.


Homework Equations


I'm not sure how to set this up so I don't know what equations to use yet.


The Attempt at a Solution


I calculated the horizontal displacement and have enough information to finish the problem, but I'm not sure which equations to use. Any start is appreciated, thanks.
 
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KE = PE

The ½mV² of the bullet becomes the mgh of the log displacement.

You know L and θ apparently so ...
 
I just figured it out. Thanks for the response though
 
Just for future reference, this page helps a lot in pendulum problems
http://www.rowan.edu/colleges/lasold/PhysicsAndAstronomy/LabManual/labs/EnergyInAPendulum.pdf
 
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