Hey there,
This is a good question that tests whether you know the components of the frictional force. Once they're written out, the process to answer this question becomes quite simple! Here are the details:
Frictional Force = Normal Force * Coefficient of friction
Now we just need to enter the data we have so that we can solve. We know the frictional force (it's in the question), and we're seeking the coefficient of friction, so we just need the normal force.
The normal force is the force the ground uses to push something upward. It comes right out of the surface that the truck is sitting on and is equal to the weight of the truck. Since we're given a mass, we need to find the weight. We do so by multiplying the mass by the force of gravity, 9.8 m/s^2. That gives us 25,176 Newtons for the weight of the truck. To keep the truck from falling through the earth, the ground has to push back on the truck at an equal force, 25,176N, and this is our normal force. Now we just need to plug in the information and solve the equation.
2,325 = 25,176* Coefficient of Friction. Then rearrange this to solve for the Coefficient and we get:
2,325/25,176 = Coefficient of Friction. Then we perform the division and get:
0.092 = Coefficient of friction.
Lastly we need to ask ourselves if this answer is reasonable. Coefficients of friction are always less than one and are usually very small. This is a very small number, so it's a reasonable answer. So there you go!
Stanton D.
This may be a normal load, in a physics sense, but it's a huge coefficient of friction for a truck! Commerically unsustainable! Suspect the truck is grossly overloaded, and scraping against the road?03/28/20