A tow-truck is trying to pull a 1.4 x 103 kg car out of some mud. The coefficient of static friction...

Question

A tow-truck is trying to pull a 1.4 x 103 kg car out of some mud. The coefficient of static friction is 0.76. What force will the tow truck have to apply to the car before it will start to move?

Answer 1

Force = μ X N

 

where μ is the coefficient of friction

 

N is the Normal Force

 

N = 1.4 X 103 X g

 

where g is the gravitational acceleration = 9.8 meters/sec

 

Force = .76 X 1.4 X 103 X 9.8 = 1074 Newtons

 

So the force has to be greater than 1074 Newtons.