- #1
AlexPilk
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Homework Statement
Mass of the bus is 20 tons. It accelerates to 10 m/s (from initial speed of 0) in 50 meters. Find the coefficient of friction (u) if the force, that pushes the bus = 14*10^3 N
m=20t=20000kg
S=50m
v=10m/s
F=14kN=14000N
The Attempt at a Solution
So we can find out what the acceleration is using
a=2S/v^2
And it will be equal to 1 m/s^2
But, the total force F(total)=F-F(friction)=m*a=14000-F(friction)=20000
So it turns out Force of friction = -4kN. How can this be, what did I do wrong?