# Homework Help: Statics question (is this possible?)

1. Mar 9, 2016

### goonking

1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution
for part b, where the angle is 45 degrees.

would this mean that if you unpin the frame at point A, it would stay completely stationary (assuming the frame is massless)?

Last edited: Mar 9, 2016
2. Mar 9, 2016

### BvU

Yes (frame weightless ?)

What's the attachment for ?

3. Mar 9, 2016

### goonking

Whoops, attachments were added by mistake.

But very interesting to know that it would be stationary. Very hard to imagine it because it is impractical.

4. Mar 9, 2016

### BvU

Impractical in the sense that it isn't a stable equilibrium, but yes: a normal force $20\;{1\over 2} \sqrt2$ at E balances the load forces.

Again, the frame weight should be zero or else the weight will make it go downhill mucho quicko !

5. Mar 9, 2016

### goonking

Yes, I spent a good minute wondering how the frame would stay stationary on a roller, on a slope because the question didn't mention the frame was massless.

6. Mar 9, 2016

### BvU

As long as they don 't mention the frame mass you should be OK. Witness the book solution (or is it yours?).

7. Mar 9, 2016

### goonking

I posted the textbook solution.

8. Mar 9, 2016

### BvU

I kind of knew that. The (my) humour is in the sleek way you evade the PF rule that an attempt at solution is required. Never mind. You have a very sensible question about a not so sensible exercise. Time to move on to the next one !

9. Mar 9, 2016

### goonking

haha, yeah, sorry, I should have posted my attempt but figured the textbook solution was much easier to read and my question was conceptual instead of asking if I had the right answer.

10. Mar 9, 2016

### BvU

All understood, clear and fine. Time to move on to the next exercise !