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jchojnac
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Homework Statement
A bullet of mass 0.125 kg traveling horizontally at a speed of 250 m/s embeds itself in a block of mass 3.5 kg that is sitting at rest on a nearly frictionless surface.
(a) What is the speed of the block after the bullet embeds itself in the block?
v = ? m/s
(b) Calculate the kinetic energy of the bullet plus the block before the collision:
Ki = ? J
(c) Calculate the kinetic energy of the bullet plus the block after the collision:
Kf = ? J
d) Was this collision elastic or inelastic?
inelastic
(e) Calculate the rise in thermal energy of the bullet plus block as a result of the collision:
Ethermal,bullet + Ethermal,block = ? J
(f) Which of the following statements are true?
The bullet and block got hot because Q was large.
Because the process was very fast, Q was negligible.
Q was negative during the collision because the bullet and block were hotter than the surroundings.
Homework Equations
delta p1+delta p2=0
delta K=0
The Attempt at a Solution
For a.) i tried 2(m/M)v but it was wrong.