What angles produce a net torque of 1250 Nm on an angled arm?

AI Thread Summary
The discussion revolves around calculating the net torque of 1250 Nm on an angled arm using various forces. The user attempts to solve the problem using torque equations but consistently arrives at different torque values, including 983.3 Nm and 793.3 Nm, indicating a misunderstanding of the lever arms involved. They explore different angles and the application of the sine function but struggle to find the correct configuration for the forces at the end of the pipe. A suggestion is made to reconsider the lever arms for the forces to achieve the desired torque. The conversation highlights the importance of accurately defining the position vectors and angles in torque calculations.
draupe
Messages
2
Reaction score
0

Homework Statement



Presentation2.jpg
My teacher gave us a solution of + 1250 Nm Where CCW = positive torque
I know that the torque of the 600N + 300N forces + 1250Nm = the torque of the 500N force.
I can't figure out what angles work with the forces at the end of the pipe.

Homework Equations


Σ T = 1250 Nm
T =Fr sinΘ

The Attempt at a Solution


ΣT = (500N x5.5m) - (600N x 1m) - (300N x 5.5m x sin 45°)

ΣT = (2750Nm) - (600Nm) - (1166.7 Nm)

ΣT = +983.3 Nm This is the answer I get when I attempted the problem.

I've also tried setting those forces with the hypotenuse as the r for the 500 and 300 N forces.
The triangle would be 4.58m base, 1.58m height. Pythagoras would say this triangle's last side( hypotenuse) would be 4.84m.

Also I tried sin of 135° turns out it is equivalent to sin 45°

ΣT = (500N x 4.84m) - (600N x 1m) - (300N x 4.84 x sin 45°)

ΣT = 2420Nm - 600Nm - 1026.7 Nm

ΣT = 793.3 Nm
 

Attachments

  • Presentation2.jpg
    Presentation2.jpg
    13.1 KB · Views: 581
Physics news on Phys.org
draupe said:
ΣT = (500N x5.5m) - (600N x 1m) - (300N x 5.5m x sin 45°)
I don't get 5.5 m for the x component of the position vector of the tip. Also 5.5m x sin 45° m is not what you should be multiplying 300 N with. You need to rethink the lever arms.
 
  • Like
Likes draupe
Thanks that helped immensely
 
Thread 'Collision of a bullet on a rod-string system: query'
In this question, I have a question. I am NOT trying to solve it, but it is just a conceptual question. Consider the point on the rod, which connects the string and the rod. My question: just before and after the collision, is ANGULAR momentum CONSERVED about this point? Lets call the point which connects the string and rod as P. Why am I asking this? : it is clear from the scenario that the point of concern, which connects the string and the rod, moves in a circular path due to the string...
Back
Top