How to Calculate Muzzle Speed in an Inelastic Collision?

AI Thread Summary
To calculate the muzzle speed of a bullet in an inelastic collision, one can use the conservation of momentum and kinematic equations. The bullet embeds into a block of wood, and the kinetic friction between the block and the surface affects its motion after the collision. The block travels 8.5 meters before coming to rest, allowing the use of Newton's second law to find the acceleration due to friction. By determining the initial velocity of the block post-collision and applying momentum conservation, the muzzle speed can be calculated. Conservation of energy is not applicable in this scenario due to the inelastic nature of the collision.
AeroFunk
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A 16 g bullet strikes and becomes embedded in a 1.30 kg block of wood placed on a horizontal surface just in front of the gun. If the coefficient of kinetic friction between the block and the surface is 0.22, and the impact drives the block a distance of 8.5 m before it comes to rest, what was the muzzle speed of the bullet?

Is there anthor equation i can use besides the conservation of momentum
mv=(m+M)v' I can't use conservation of energy because its inelastic right? So what can I do help please.
 
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Kinematic:

v^2 = v_{o}^2 + 2a \Delta x

and Newton's 2nd Law to get the acceleration

\sum_{i=1}^{n} \vec{F}_{i} = m \vec{a}
 
AeroFunk said:
I can't use conservation of energy because its inelastic right? So what can I do help please.
You can't use conservation of kinetic energy.
Use can use conservation of energy.
 
AeroFunk said:
A 16 g bullet strikes and becomes embedded in a 1.30 kg block of wood placed on a horizontal surface just in front of the gun. If the coefficient of kinetic friction between the block and the surface is 0.22, and the impact drives the block a distance of 8.5 m before it comes to rest, what was the muzzle speed of the bullet?

Is there anthor equation i can use besides the conservation of momentum
mv=(m+M)v' I can't use conservation of energy because its inelastic right? So what can I do help please.
Split your problem in two:
1. Assume that after the collision is finished, the system begins moving with some velocity v_{0}
Determine v_{0} with Cyclovenom's first equation.
2. You may now use momentum conservation during the collision phase to determine the muzzle speed (assuming the bullet did not meet any air resistance in the phase between it is shot out until the collision begins)
 
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