Solving Vectors and Forces Homework Problem

  • Thread starter Thread starter P.townsville
  • Start date Start date
  • Tags Tags
    Forces Vectors
AI Thread Summary
The problem involves calculating the tension in two wires supporting a 150N sign, with one wire at a 50-degree angle and the other at a 40-degree angle to the wall. Initial calculations suggested tensions of 233.36N and 195.81N for the respective wires, but these were incorrect. The correct approach requires setting up equations for both vertical and horizontal components of the forces, ensuring that the sum of the vertical components equals the weight of the sign. A hint was provided to simplify the problem by finding a direction to ignore one of the tension forces. Accurate calculations depend on applying trigonometric principles correctly to resolve the forces.
P.townsville
Messages
1
Reaction score
0

Homework Statement



A sign weighs 150n and is suspended on 2 wires between 2 walls, 1 at 50 degrees to the wall and the other at 40 deg to the other wall. What is the tension in each wire?

Homework Equations





The Attempt at a Solution



For the 1st wire F=150/cos50
=233.36N
2nd wire F=150/cos40
=195.81N
Is this likely to be correct I can't find any simular examples to help me out.
 
Physics news on Phys.org
Welcome to PF!

Hi P.townsville! Welcome to PF! :smile:

(have a degree: º :wink:)
P.townsville said:
A sign weighs 150n and is suspended on 2 wires between 2 walls, 1 at 50 degrees to the wall and the other at 40 deg to the other wall. What is the tension in each wire?

For the 1st wire F=150/cos50
=233.36N
2nd wire F=150/cos40
=195.81N

Nooo :redface:

you're saying F1cos50º = 150, F2cos40º = 150.

But if you're taking vertical components, that'll be F1cos50º + F2cos40º = 150, won't it?

Hint: you need one equation for both vertical components, and another equation for both horizontal components, and then a bit of algebra and trig. :smile:

(Alternatively, find a direction in which you can ignore one of the tension forces :wink:)
 
TL;DR Summary: I came across this question from a Sri Lankan A-level textbook. Question - An ice cube with a length of 10 cm is immersed in water at 0 °C. An observer observes the ice cube from the water, and it seems to be 7.75 cm long. If the refractive index of water is 4/3, find the height of the ice cube immersed in the water. I could not understand how the apparent height of the ice cube in the water depends on the height of the ice cube immersed in the water. Does anyone have an...
Thread 'Variable mass system : water sprayed into a moving container'
Starting with the mass considerations #m(t)# is mass of water #M_{c}# mass of container and #M(t)# mass of total system $$M(t) = M_{C} + m(t)$$ $$\Rightarrow \frac{dM(t)}{dt} = \frac{dm(t)}{dt}$$ $$P_i = Mv + u \, dm$$ $$P_f = (M + dm)(v + dv)$$ $$\Delta P = M \, dv + (v - u) \, dm$$ $$F = \frac{dP}{dt} = M \frac{dv}{dt} + (v - u) \frac{dm}{dt}$$ $$F = u \frac{dm}{dt} = \rho A u^2$$ from conservation of momentum , the cannon recoils with the same force which it applies. $$\quad \frac{dm}{dt}...
Back
Top