Raphael D. answered • 03/31/16
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The breaking distance is proportional to the initial kinetic energy (absorbed totally by friction interavtion).
So, if the speed doubled (from 80 to 160kmhr), then energy increases fourfold.
Thus, the breaking distance would be 200m.
Raphael D.
well:
friction force is constant, say F ( depending on pavement quality and car's weight).
The work done by friction force would be
F*d (with d=50m)
Same time,
F*d=E_kin=mV^2/2
so,
d=mV^2/2/F ~ V^2
or,
d1/d2=(v1/v2)^2 , with d1=80m and d2 - unknown, also v2=80/km/hr and v2=160km/hr
d2=d1*(v2/v2)^2=50(m)*(160/80)^2=50(m)*4=200(m)
take care:)
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03/31/16
Michael ..
Thank you. You too, take care.
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03/31/16
Michael ..
03/31/16