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PhysicsAdvice
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A truck with a mass of 4500kg and a car with a mass 1500kg both apply the brakes at the same time, if the coefficient of friction is 0.15, and both vehicles are traveling at 20m/s, how far will it take each vehicle to stop?
Ff=0.15Fn
W=FappD
Ek2-Ek1=W
Fn=mg
Ek=1/2mv^2
for the truck:
Fn=4500kg(-9.81m/s^2)= -44145N Ek2-Ek=0-(1/2(4500kg)(20m/2)^2)
=-900000j
Ff=0.15(-44145N)
=-6621.75N
-900000j=-6622.75N x D=135.8952097m
For Car: Fn= -24525N Ek2-Ek1=-500000j
Ff= 0.15(-24525N)=-3678.25N
-500000j=-3678.25N x D=135.9342078m
Should the distances really be the same?
Ff=0.15Fn
W=FappD
Ek2-Ek1=W
Fn=mg
Ek=1/2mv^2
for the truck:
Fn=4500kg(-9.81m/s^2)= -44145N Ek2-Ek=0-(1/2(4500kg)(20m/2)^2)
=-900000j
Ff=0.15(-44145N)
=-6621.75N
-900000j=-6622.75N x D=135.8952097m
For Car: Fn= -24525N Ek2-Ek1=-500000j
Ff= 0.15(-24525N)=-3678.25N
-500000j=-3678.25N x D=135.9342078m
Should the distances really be the same?