NEED HELP HW I really need this, it's due sooN

  • Thread starter matt000
  • Start date
In summary: For example, if you have a block of weight 1kg resting on a surface and you apply a force of 100 N to it, the static friction force will be 100 N/kg and the kinetic friction force will be 100 N/m. Since the coefficients of friction are dimensionless, they cancel each other out and the force is dimensionless.
Physics news on Phys.org
  • #2
What particular questions are you trying to answer? You need to show some effort before we can help you!
 
  • #3
gah sorry!

trufthfully, I don't exactely know how to start...
um.. it's just the equation is odd to me. The book said that static friction is supposed to be dimensionless...
F<(or eqaul to) U(s)N..

How in the WORLD does this even work?!
 
  • #4
matt000 said:
um.. it's just the equation is odd to me. The book said that static friction is supposed to be dimensionless...
F<(or eqaul to) U(s)N..
The coefficient of friction is dimensionless, not the friction force itself.

This equation tells you how to calculate the maximum value of static friction between two surfaces, which depends on the nature of the surfaces (given by the coefficient of friction) and how hard they are being squeezed together (given by the normal force).
 
  • #5
If one has a box or block resting on a flat surface, one will find that the force (push) is greater than the force to sustain movement. This is because the static friction is greater than the kinetic friction, which implies the coefficient of static friction is greater than that of kinetic friction.

The force of friction 'acts' tangentially to the contact surface (i.e. in shear) and is proportional to the normal force, e.g. weight (force of gravity) of an object. The proportionality constant is the 'coefficient of friction.'
 
  • #6
matt000 said:
F<(or eqaul to) U(s)N..

How in the WORLD does this even work?!

Lets say you apply a force to move a block. You start with a light force and the block doesn't move. You push a little harder and it still doesn't move. Finally, you reach a point where you have applied a great enough force to get the block moving. In the first 2 cases, the force applied was less than the maximum static friction force. The force of friction balanced the applied force in these cases. It can take on any value in this range. Then after you exceed the maximum static friction force, a net force is created which moves the block. Note that its easier to keep the block moving once you get it started. This is because the coefficient of kinetic (sliding) friction is less than the coefficient of static (starting) friction
 
  • #7
Good clear explanation, Turdferguson. And the reason it's dimensionless is because it's a ratio of two forces -- all the units cancel each other out.
 

1. What is the best way to ask for help with my HW?

The best way to ask for help with your HW is to be specific about what you need assistance with. Provide details about the assignment, including the due date and any specific instructions or requirements. Also, be sure to ask for help from someone who is knowledgeable and qualified in the subject matter.

2. How do I manage my time effectively to finish my HW on time?

To manage your time effectively, it's important to create a schedule and stick to it. Break down your HW into smaller tasks and allocate specific times for each task. Prioritize your assignments and make sure to allow enough time for breaks and rest. Also, avoid procrastination and start working on your HW as soon as possible.

3. Can someone help me with my HW last minute?

While it's always best to ask for help as early as possible, there are still ways to get assistance with your HW last minute. Consider reaching out to a tutor, classmate, or teacher for help. You can also try using online resources or seeking help from a study group. Just remember to be respectful of others' time and not wait until the very last minute to ask for help.

4. How can I make sure I understand the material for my HW?

To ensure that you understand the material for your HW, it's important to actively engage in the learning process. Take thorough notes during lectures, ask questions when you don't understand something, and review your notes regularly. Also, try to apply the material to real-life situations to solidify your understanding.

5. What should I do if I still don't understand my HW even after seeking help?

If you are still struggling with your HW even after seeking help, don't hesitate to reach out to your teacher or professor for further clarification. They are there to help you and may be able to provide additional resources or explanations to help you better understand the material. Additionally, consider studying with a group or seeking help from a tutor to get a different perspective on the material.

Similar threads

Minimal rotational kinetic energy for a gyroscope to precess
    • Introductory Physics Homework Help
Replies
33
Views
947
A ball climbing a ramp while "rolling the wrong way"
    • Introductory Physics Homework Help
Replies
32
Views
2K
Need help on my physics hw - vectors
    • Introductory Physics Homework Help
Replies
5
Views
1K
Help Needed with Homework: 3-2-1 Due Monday!
    • Introductory Physics Homework Help
Replies
1
Views
1K
I need some help for the verification of an assignment about pendulums
    • Introductory Physics Homework Help
Replies
2
Views
1K
Slipping Ladder Angular Acceleration
    • Introductory Physics Homework Help
Replies
5
Views
3K
Other Math Help for Physics Undergrad: Advice Needed
    • STEM Academic Advising
Replies
9
Views
1K
Car on a hill - reasoning for static friction
    • Introductory Physics Homework Help
Replies
5
Views
5K
Help critique my problem solving and thinking process (problem included)
    • Introductory Physics Homework Help
Replies
6
Views
1K
Need help on these problems soon
    • Introductory Physics Homework Help
Replies
2
Views
3K

Hot Threads

Recent Insights

Back
Top