# Moment with two unknown forces

1. Jul 11, 2017

### Buns_of_Steel

• Member advised to use the homework template for posts in the homework sections of PF.
Ok here goes. It's been a long time since i've done anything like this and i just cant remember what to do.

I'e got a beam 167.5mm long. It is supported at 24.5mm along the beam.

6600kgf acts at one end of the beam.

F1 acts at 128.5mm along the beam. F2 acts at 167.5mm along the beam.

F1 and F2 are different and the beam is balanced.

How do i calculate F1 and F2?

Cheers

2. Jul 11, 2017

### CWatters

You posted in the homework section so should use the template.

It's a static problem so the net force is zero and the net torque about any point is zero.

3. Jul 12, 2017

### Universeer

It's a static problem so the net force is zero and the net torque about any point is zero.[/QUOTE]

I agree with static problem thing.
But how can we get F1 and F2.

4. Jul 12, 2017

### jbriggs444

You have to show some work before we are allowed to help you.

5. Jul 12, 2017

### Staff: Mentor

I agree with static problem thing.
But how can we get F1 and F2.[/QUOTE]
Let's see your force- and moment balance equations.

6. Jul 12, 2017

### CWatters

As there are two unknowns (F1 and F2) you will need two simultaneous equations. See my post #2 for a hint.

7. Jul 16, 2017

### PhanthomJay

Looks like 3 unknowns. The single support reaction is an unknown. There is no specific solution. If the problem is stated correctly.

Last edited: Jul 16, 2017
8. Jul 17, 2017

### CWatters

On reading the OP again I think I agree.

9. Jul 17, 2017

### Staff: Mentor

It's worse than that. The problem doesn't state how the forces F1 and F2 are acting: Are they both acting upwards? One up one down? Something else? Which end of the beam is the 6600 kgf acting?

I'm very tempted to simply delete the thread and ask the OP to start over with a full disclosure of the original question in its original form (and to use the template, of course).

10. Jul 17, 2017

### CWatters

I wouldn't delete it. I think better to close it until the OP responds to your PM.