Car crash stimulus calculations

AI Thread Summary
In a car crash scenario, car A is stationary at traffic lights while car B approaches at 100 km/h, equating to a velocity of 27.8 m/s. Car B has a deceleration of -6.7 m/s² and a weight of 1385 kg, while the weight of car A is unknown. The thinking distance for car B is calculated at 41.7 m. The user is attempting to calculate momentum, force, coefficient of friction, and velocity but is confused about the conservation of momentum, noting that the momentum before the collision appears greater than after. Assistance is requested to clarify these calculations.
omgplshelpme
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there is a car crash where car A is resting at the traffic lights and car B is driving at 100km/hr and at 45m saw the car and stepped on the brakes.

the velocity of car B is 27.8m/s
the deceleration is -6.7 m s^-2
the thinking distance is 41.7m
weight of car B is 1385 kg
weight of car A is x

i have to calculate the momentum, force, coefficient force and velocity etc...

i really need help

ty
 
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hi omgplshelpme! welcome to pf! :smile:

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Show us what you've tried, and where you're stuck, and then we'll know how to help! :smile:
 
ok i have calculated the momentum of both cars and the momentum before the collision is greater then the momentum after the collision, have i done something wrong? momentum before is suppose to equal momentum after

ah I am so confused
 
hi omgplshelpme! :wink:

show us your full calculations :smile:
 
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