In: Physics
Brakes are applied to a 3000-kg car moving at 30 m/s. The car skids 200 m and stops. What is the coefficient of kinetic friction?
Clarification:
1)since displacment and friction direction are opposite we have used angle 180
2)you could have used g=9.8m/s2, it will not affect much answer would have been 0.459
3)yes you are correct mass here was given just to distract it has no use here.
4)as there is no motion along vertical axis we have N=Mg.
A Using Work Energy Theorm, no V-0 (Stokes ds Grivena u = 30mis V=0 (s) distance of skid = 200m Mass of car = 3000 kg . Now casi esing them. Fora M N Mng of ficti ion (f) fesher u is kinetic friction coefficient). W Kf - Ki Ith L mo? 2 SEAS mu Tung ds con180 MM g Sos I m(o)²-mo² 2 I Mu? ung s & MO² 2 M = U² (30) sg 200 X 10 Taking = 0.45 g=10m/a2)