How Do Magnetic Forces Between Parallel Current-Carrying Wires Impact Wire I1?

  • Thread starter Thread starter darwin59
  • Start date Start date
  • Tags Tags
    Infinite Wires
AI Thread Summary
The discussion focuses on calculating the x-component of the magnetic force exerted on wire I1, which carries a current of 3.3 A in the negative z-direction. The relevant equations include Biot-Savart's Law and the formula for magnetic force between parallel wires. The user initially attempted to calculate the magnetic fields and forces individually before combining them, resulting in an incorrect force value. After realizing the error stemmed from using a different calculator, they confirmed their approach was correct. The conversation highlights the importance of accurate calculations in physics problems involving magnetic forces.
darwin59
Messages
12
Reaction score
0

Homework Statement


Three infinite straight wires are fixed in place and aligned parallel to the z-axis as shown. The wire at (x,y) = (-23.5 cm, 0) carries current I1 = 3.3 A in the negative z-direction. The wire at (x,y) = (23.5 cm, 0) carries current I2 = 1.2 A in the positive z-direction. The wire at (x,y) = (0, 40.7 cm) carries current I3 = 7.9 A in the positive z-direction.

http://www.smartphysics.com/images/content/EM/14/h14_threewires.png

What is Fx(1), the x-component of the force exerted on a one meter length of the wire carrying current I1?

Homework Equations


Biot-Savart's Law: B=\frac{μ_{o}I}{2∏r}
Magnetic Force: F=ILxB
F=\frac{μ_{o}I_{1}I_{2}L}{2∏r}

The Attempt at a Solution


I've tried using B-S to find each magnetic field individually, then find their forces individually, then combined together to get the total force. Using the arctan, I can get the angle of the force from the x-axis, which allows me to get the force in the x direction. I've also tried combining the fields together first and finding the angle then. I then use the force from the field. In both situations I'm getting a force of 7.138e-5N in the negative x direction, but apparently I'm wrong.
 
Last edited by a moderator:
Physics news on Phys.org
I figured out my problem. I was actually doing it right, but I'm using a different calculator, so I was inputing numbers wrong.
 
I currently am on this problem with my homework. I thought this was correct. Thank you for the reassurance.
 
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