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A 1200 kg car going 30 m/s skids to a rest.

The friction force is 6000 N. How far does it skid?

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Brad M. | Professional Tutor: STEM plus Business, Accounting, and InvestmentProfessional Tutor: STEM plus Business,...
4.9 4.9 (219 lesson ratings) (219)
Hey again, Sierra -- braking decel is 6000N/1200kg = 5 m/s/s taking 6 secs to stop ...
ave speed of 15m/s moving for 6 sec travels 90m ... Regards :)
Grigori S. | Certified Physics and Math Teacher G.S.Certified Physics and Math Teacher G.S.
Because the car completely stops you can apply the standard formula connecting the acceleration, distance traveled, initial and final speed. Let "a" be the acceleration, vi = 30m/s (initial speed), vf = 0 -final speed, F -force of friction,  "m" - mass. If the distnace traveled is "d", then we have
                                  2ad = vf2 - vi2 = -900 m2/s2
The force of friction is acting in opposite direction. Thus,
                       aF/m = - 6000 N/1200 kg = - 5m/s2
We obtain for d (after canceletaions)
                             d = 900m/2x5 = 90 m
Andre W. | Friendly tutor for ALL math and physics coursesFriendly tutor for ALL math and physics ...
5.0 5.0 (3 lesson ratings) (3)
Numerical answer only please... :)
90 m
(see your previous problem)