Magnetic field, current, and a slide wire

In summary, the question asks for the terminal velocity of a slide wire with given parameters (l = 25.0 cm, m = 10.0 g, R = 0.100 ohms, and B = 0.550 T) sliding up and down a vertically oriented conducting rail in a horizontal magnetic field. The formula V_emf = vlB can be used to determine the velocity, but the question does not provide V_emf. However, using the formula F = IlB and P = Fv = (v^2)(l^2)(B^2)/R, the terminal velocity can be found by solving for I and then substituting it into V_emf = vlB. The relevance
  • #1
Heart
39
0
Hi, I really need help with this question.

Here's the question:

"The figure shows a U-shaped conducting rail that is oriented vertically in a horizontal magnetic field. The rail has no electric resistance and does not move. A slide wire with mass m and resistance R can slide up and down without friction while maintaining electrical contact with the rail. The slide wire is released from rest."

"Determine the value of a terminal velocity if l = 25.0 cm, m = 10.0 g, R = 0.100 ohms, and B = 0.550 T."

I know that V_emf = vlB
I = V/R = vlB/R
If I can find I, then I could determine v. The problem is they don't give V_emf, so I cannot find I. and I have no idea why would they give the mass for, when generally for this type of problem they don't. Any hints would be greatly appreciated.
 

Attachments

  • knight.jpg
    knight.jpg
    5.8 KB · Views: 776
Physics news on Phys.org
  • #2
F = IlB
P = Fv = (v^2)(l^2)(B^2)/R

I just don't see how could the mass be relevant to this problem. If it was a particle then may be I could use the mass to do something with the circular motion but this just doesn't make sense. Please help.
 
  • #3
I think I might get it now, I just didn't read the question carefully and miss the "vertical part".
 
  • #4
:eek: OK, I got it, still cannot believe I could miss the keyword "vertical". Thanks and sorry for this. Please don't get mad at me. I'm going to sleep now at almost 8 A.M. :zzz:
 

1. What is a magnetic field?

A magnetic field is an invisible force that surrounds a magnet or a moving electric charge. It is created by the movement of electrons within an object and is responsible for the attraction or repulsion of other magnetic objects.

2. How is a magnetic field measured?

A magnetic field is measured in units of Tesla (T) or Gauss (G) using a device called a magnetometer. It works by detecting the strength and direction of the magnetic field lines.

3. What is the relationship between current and magnetic fields?

A current flowing through a wire creates a magnetic field around the wire. The strength of the magnetic field is directly proportional to the amount of current flowing through the wire.

4. What is a slide wire and how is it used?

A slide wire is a long, thin wire that is used to create a closed loop circuit for conducting electricity. It is often used in experiments to study the effects of current and magnetic fields on each other.

5. How can a slide wire be used to generate electricity?

A slide wire can be used to generate electricity by moving it through a magnetic field. As the wire cuts through the magnetic field, a current is induced in the wire, creating an electrical potential that can be harnessed to power devices.

Similar threads

  • Introductory Physics Homework Help
Replies
3
Views
1K
  • Introductory Physics Homework Help
Replies
14
Views
1K
  • Introductory Physics Homework Help
Replies
16
Views
381
  • Introductory Physics Homework Help
Replies
3
Views
998
  • Introductory Physics Homework Help
Replies
11
Views
1K
  • Introductory Physics Homework Help
Replies
7
Views
1K
  • Introductory Physics Homework Help
Replies
2
Views
261
  • Introductory Physics Homework Help
Replies
1
Views
142
  • Introductory Physics Homework Help
Replies
2
Views
722
  • Introductory Physics Homework Help
Replies
5
Views
2K
Back
Top