# Static Friction Coefficient Problems

1. Feb 27, 2013

### jklops686

1. The problem statement, all variables and given/known data
There are 2 questions in the attachments both with the same scenario I'm having troubles with.

2. Relevant equations

f=ma

3. The attempt at a solution
I tried finding the budging force between the 2 masses and that was about 4. I don't know where to go from there to find the acceleration.

#### Attached Files:

File size:
25.8 KB
Views:
81
• ###### question2.jpg
File size:
26.3 KB
Views:
71
2. Feb 27, 2013

### rude man

Afraid I'm no help since I picked an answer for part 1 which does not correspond to any of the choices for answers in part 2.

Anyone else?

3. Feb 27, 2013

### jklops686

there is still one answer choice that isn't shown. couldn't get it in the screen shot

4. Feb 27, 2013

### ap123

What was the last answer choice? (for both problems)

You've already worked out the maximum frictional force that can be on the 2kg object - 4N.
Since this is the only horizontal force on the object, then this is also the maximum net force on it.
So, just use F=ma to get the maximum acceleration.

( If this is not the hidden answer, then I will have to rethink it ).

5. Feb 27, 2013

### rude man

But 4N is not the F shown on the picture. (I agree it's the force on the 2 kg block.)

I picked one of the visible answers for part 1 but not for part 2 so my hope is for the remaining choice of part 2 to be my answer.

We need those last two answers jklops!

6. Feb 27, 2013

### haruspex

ap123 wrote that his / her answer for the acceleration corresponded to a force of 4N on the top block.
jklops686, what do you get for F?