Need help finding change in velocity and momentum

AI Thread Summary
An automobile collision involving two 1500 kg vehicles results in a change of momentum and speed due to friction. The friction force calculated is 18541 N, leading to a change in momentum of 371 kg*m/s over 0.020 seconds. The initial momentum is 36000 kg*m/s, resulting in a final momentum of 35629 kg*m/s. The change in speed is determined to be 0.15 m/s. The calculations were confirmed to be correct after adjusting the mass used in the equations.
Sneakatone
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An automobile of mass 1500 kg traveling at 24 m/s crashes into a similar parked automobile. The two automobiles remain joined together after the collision. Suppose that the collision last for 0.020s, and pavement with a coefficient of friction uk=0.63. What change of momentum and what change of speed does the friction force produce in the joined automobiles in the interval of 0.020 s ?

Delta p=?
Delta v=?

for p I did 24m/s *1500kg=36000
3600/12m/s=3000
The Friction force = µ . m . g =0.63*9.81*3000=18541 N
The change in momentum produced by this force = F . t =18541*0.02=371 kg*m/s
delta p=36000-371=35629 kg*m/s

to get v
35629/3000=11.87m/s
12m/s-11.87m/s=0.15 m/s
 
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What exactly do you need help with?
 
the numbers that I input are apparently wrong.
 
I am not sure what you mean by this. I have checked your computations and my results agree with yours.
 
Sneakatone said:
The Friction force = µ . m . g =0.63*9.81*3000=18541 N
Does the offending vehicle have its brakes on?
 
it does not
 
Sneakatone said:
it does not

So... what's the error in the equation I quoted?
 
I should have used 1500kg for mass instead.
 
Sneakatone said:
I should have used 1500kg for mass instead.
Exactly. Does it accept your answer now?
 
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