Ladder Equilibrium: Solving for Forces at Hinged Point?

  • Thread starter Thread starter azwraith69
  • Start date Start date
  • Tags Tags
    Equilibrium
AI Thread Summary
The discussion revolves around solving for forces at the hinged point of a ladder in equilibrium. The user is attempting to apply the principles of net force and net torque to analyze the system but is struggling with the forces exerted by the hinge. A suggestion is made to choose a pivot point that avoids the need to consider hinge forces, which helps simplify the problem. The user acknowledges this advice and calculates the normal force as 150N. The conversation emphasizes the importance of strategic pivot selection in solving equilibrium problems.
azwraith69
Messages
7
Reaction score
0

Homework Statement


see the attachment below...

Homework Equations


net force = 0, net torque = 0
normal force(ground) = ?

The Attempt at a Solution


well, so far,,

net force(y) = normal force(floor) - weight(man) - weight(ladder) + ??(force exerted by hinge?)
net force(x) = 0 ( ?? )

Choosing the bottom of ladder as pivot point,
net torque = weight(ladder) x 2a + weight(man) x a - ??(force by hinge?)

First of all, sorry for not using latex..

The hinge is my problem, since I'm not familiar in solving with it.
What are the forces (and their directions) exerted on the ladder at the hinged point?
I really don't know..

And are my assignment of forces correct?

Thanks in advance..

I NEED THIS AFTER 10 HOURS...
So i have no time to reply, so please, I'm begging, please be direct to the point. And i hope each reply will help me..

Thank you guys..
 

Attachments

Physics news on Phys.org
Hint: Choose a pivot point that eliminates having to know anything about the forces at the hinge.
 
Doc Al said:
Hint: Choose a pivot point that eliminates having to know anything about the forces at the hinge.

thanks... i overlooked it since i always choose the point of contact with the ground as the pivot..

normal force = 150N ??

:)
 
You got it. :approve:
 
I multiplied the values first without the error limit. Got 19.38. rounded it off to 2 significant figures since the given data has 2 significant figures. So = 19. For error I used the above formula. It comes out about 1.48. Now my question is. Should I write the answer as 19±1.5 (rounding 1.48 to 2 significant figures) OR should I write it as 19±1. So in short, should the error have same number of significant figures as the mean value or should it have the same number of decimal places as...
Thread 'A cylinder connected to a hanging mass'
Let's declare that for the cylinder, mass = M = 10 kg Radius = R = 4 m For the wall and the floor, Friction coeff = ##\mu## = 0.5 For the hanging mass, mass = m = 11 kg First, we divide the force according to their respective plane (x and y thing, correct me if I'm wrong) and according to which, cylinder or the hanging mass, they're working on. Force on the hanging mass $$mg - T = ma$$ Force(Cylinder) on y $$N_f + f_w - Mg = 0$$ Force(Cylinder) on x $$T + f_f - N_w = Ma$$ There's also...
Back
Top