Calculating Stopping Force for a 850kg Car at 110km/h | Physics Question

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To calculate the stopping force for an 850kg car traveling at 110km/h and brought to rest in 10 seconds, one can apply the impulse-momentum principle or kinematics. The average force can be determined using the formula F_avg * Δt = m * Δv, where Δv is the change in velocity. The discussion clarifies that the question specifically seeks the force required to stop the car, rather than external forces like friction or wind. Understanding impulse and momentum is crucial, but kinematics can also be used to find the necessary acceleration and subsequently the stopping force. The emphasis is on determining the magnitude of the constant force needed to achieve this stop within the given timeframe.
physicsgrade11
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ok here is the question exaclty- its worth 5 marks so i don't know what I am missing..

A car with a mass of 850kg is moving in a straight line at a constant speed of 110km/h. It is brought to rest in 10.0s. What constant force is acting to stop the car?
 
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F_{avg}\Delta t = m\delta v
 
Looks like an impulse question.
 
Thanks anyways guys but i got it. I think i was thinking it was asking what force as in friction or wind etc. was stopping it but its asking the force it would take to stop it in that time.
 
If you are not familiar with impulse/momentum, you can always use kinematics to find the acceleration, then apply Newton's 2nd law to find the force.
 
Good point...I guess they should have said "determine the magnitude of the constant force that brings the car to a stop".
 

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