Finding the magnitude of force P

[Touran Khan]

Homework Statement

Homework Equations

F = ma

The Attempt at a Solution

My value for P does not make any sense. Why is this so?

 

[TomHart]

I think you may have forgotten one of the vertical forces.

 

[Touran Khan]

I think you may have forgotten one of the vertical forces.

Yeah, I'm almost certain that's the issue. I think it's the normal force, but what is the value of that force in this case?

 

[TomHart]

Yes, you forgot the normal force when you summed the vertical forces. But I don't know what the value of that force is. You will just have to use a variable, F_N, until you solve the equations and find its value.

 

[Touran Khan]

Yes, you forgot the normal force when you summed the vertical forces. But I don't know what the value of that force is. You will just have to use a variable, F_N, until you solve the equations and find its value.

Oh right, my bad. So for vertical forces my equation ends up being Psin10 - 70cos45 + Fn = 0. From the horizontal forces equation I calculated P to be 57.369...

Then, Fn = 39.535...

To sum it up, P = 57.4 and Fn = 39.54. These values satisfy both equations, though do you have any idea what reaction force they are referring to?

 

[TomHart]

That looks right. I'm not sure but "reaction force", probably means the normal force.

 

[Touran Khan]

That looks right. I'm not sure but "reaction force", probably means the normal force.

Alright that's what I was thinking as well, no idea what else it could be. Thanks for the help.