The shortest distance in which you can stop an automobile by locking the brakes when traveling at 31.3 m/s is 62.48m
Force of friction f=N=mg,
where m is the mass of the car.
Acceleration,
a=f/m=mg/m=g
=0.8 x9.8
=7.84m/s2
The distance travelled, S before coming to rest (v = 0)
S=(v2- u2)/2
=(0 - 31.3x31.3)/2x7.84
=62.48 m
The shortest distance in which you can stop an automobile by locking the brakes when traveling at 31.3 m/s is 62.48m
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