Experimentally Determine Coefficient of Static Friction

chrissyinbloom

I need to determine the coefficient of static friction for the following set-up.

M1 = 380.45g
M2 = 74.7g

This is what I know... u=F/mg

What I can't figure out is how to factor in the horizontal and vertical weights.

Can anyone help?

Thanks!

Attachments

• 284.4 KB Views: 281
Related Introductory Physics Homework Help News on Phys.org

chrissyinbloom

I should clarify.. those weights are the weights where the system just begins to move.

Doc Al

Mentor
Hint: What does the tension in the string equal?

chrissyinbloom

OK, the tension for both is the same.. and it is equal to.... M2g I think ?

I'll keep thinking on this..

Thanks

Doc Al

Mentor
Right. There's a single tension in the string and it equals $M_2g$.

So, what must the friction force equal?

chrissyinbloom

OK, here's what I think... the force must equal the tension (M2g), which is equal to uN.

What is N then? The mass of M1??

Doc Al

Mentor
OK, here's what I think... the force must equal the tension (M2g), which is equal to uN.
Good!

What is N then? The mass of M1??
Not the mass but the weight of M1.

chrissyinbloom

Yes, the weight!

Thanks a bunch for your help!

Physics Forums Values

We Value Quality
• Topics based on mainstream science
• Proper English grammar and spelling
We Value Civility
• Positive and compassionate attitudes
• Patience while debating
We Value Productivity
• Disciplined to remain on-topic
• Recognition of own weaknesses
• Solo and co-op problem solving