Solve Friction Problem: Find Car Mass and Normal Force

  • Thread starter BluE
  • Start date
  • Tags
    Friction
In summary, the conversation discusses the problem of finding the mass and normal force of a car moving down a slope when the brakes are applied. The given information includes the slope angle, applied force, coefficient of kinetic friction, and gravity. The conversation also mentions the use of a free body diagram and resolving components to solve the problem. The conversation concludes with the individual thanking everyone for their help.
  • #1
BluE
23
0
Hi, I got stuck on this and need help...

The most massive car ever build was the official car of the General Secretary of the COmmunitst party in the former Soviet Union. Suppose this car is moving down a 10.0º slope when the driver suddenly applies the brakes. The net force acting on the car as it stops is -2.00 x 10^4 N. If the coefficient of kinetic friction between the car's tires and the pavement is 0.797, what is the car's mass? What is the magnitude of the normal force that the pavement exerts on the car?

So, the given info are:
theta = 10 degrees
force, applied = -2.00 x 10^4 N
and mew k = 0.797
gravity = 9.81 m/s^2

Is that right? Now this is where I'm stuck.. I'm not sure what I need to find first and the equations to use to find it...

Please help... thank you!
 
Physics news on Phys.org
  • #2
Draw an free body diagram remembering the fact that the normal force will be applied normal to the surface. Have you solved any sliding questions before using friction?
 
  • #3
Yes, I've drawn a free body diagram, but I'm not sure how to solve it now.

I have not solved questions using friction before.

Do I need to find the x and y components and go from there?
 
  • #4
Yes, you need to resolve components so that they are all either parallel or perpendicular to the inclined plane.
 
  • #5
Alright, I've gotten it. Thank you, everyone.
 

Related to Solve Friction Problem: Find Car Mass and Normal Force

1. What is friction and why is it important to solve friction problems?

Friction is a force that opposes the motion between two surfaces that are in contact. It is important to solve friction problems because understanding and controlling friction is essential in many scientific and engineering applications, such as designing efficient machines and reducing wear and tear on surfaces.

2. How do you calculate the mass of a car using friction?

To calculate the mass of a car using friction, you first need to measure the coefficient of friction between the car's tires and the surface it is traveling on. Then, you can use the formula Ff = μFn, where Ff is the force of friction, μ is the coefficient of friction, and Fn is the normal force. Lastly, you can use the formula Fg = mg, where Fg is the force of gravity, m is the mass of the car, and g is the acceleration due to gravity. By equating these two formulas, you can solve for the mass of the car.

3. What is the normal force and how does it relate to friction?

The normal force is the force that a surface exerts on an object that is in contact with it. It is always perpendicular to the surface and acts to support the weight of the object. In the context of friction, the normal force is important because the force of friction is directly proportional to the normal force. This means that as the normal force increases, so does the force of friction.

4. Can you solve a friction problem without knowing the coefficient of friction?

Yes, it is possible to solve for the mass and normal force in a friction problem without knowing the coefficient of friction. This can be done by using other known values, such as the force of friction or the angle of incline, and applying the appropriate formulas.

5. How can solving friction problems help in real-life situations?

Solving friction problems can help us understand and predict the behavior of objects in real-life situations. For example, it can help engineers design more efficient machines, improve the performance of vehicles, and reduce the amount of wear and tear on surfaces. It can also help in everyday situations, such as understanding how to safely push or lift objects, or how to prevent slipping on a wet surface.

Similar threads

  • Introductory Physics Homework Help
Replies
9
Views
3K
  • Introductory Physics Homework Help
Replies
8
Views
858
  • Introductory Physics Homework Help
Replies
15
Views
1K
  • Introductory Physics Homework Help
Replies
5
Views
1K
  • Introductory Physics Homework Help
Replies
6
Views
2K
  • Introductory Physics Homework Help
Replies
2
Views
1K
  • Introductory Physics Homework Help
Replies
7
Views
3K
  • Introductory Physics Homework Help
Replies
6
Views
2K
  • Introductory Physics Homework Help
Replies
5
Views
1K
  • Introductory Physics Homework Help
Replies
10
Views
4K
Back
Top