# I "stickyness" and friction?

1. Oct 26, 2016

### LLT71

is "stickyness" part of the static friction? is it already integrated in coefficient of static friction μ or there is some special case where you put "coefficient of stickyness" in formula μ*N when things get sticky? I imagine peace of tape on some flat, relatively smooth surface. you have to pull it with relatively high amount of force in order to set it in linear motion. I suppouse area of that peace of tape also has some significance by means larger the peace of tape is larger the static friction would be?

2. Oct 26, 2016

### maughanster

I believe that you could just increase the coefficients of friction (static or otherwise) to compensate for the "stickyness". I have not yet run into coefficients of stickyness in my studies. Just coefficients of friction. Are you working on anything specific, or just curious.

3. Oct 27, 2016

### A.T.

That simple model doesn't really apply to adhesive tape, which can stick even when N=0 or even N<0.

4. Oct 27, 2016

### LLT71

just curious :D I had the same idea about compensation for example that miu can be much grater than one.

could you explain me a bit about that N=0 and N<0 cases, I am just curious, and how N can be less than zero? thanks!

5. Oct 27, 2016

### A.T.

6. Oct 27, 2016

### LLT71

7. Oct 27, 2016

### A.T.

"The normal force is defined as the net force compressing two parallel surfaces together;..."

What does negative compression mean?

8. Oct 27, 2016

### LLT71

sorry I have very poor physics knowlege

9. Oct 27, 2016

### A.T.

Do you understand what "compressing" or "pressing" means? What is the opposite of that?