Aqa Physics Electromagnetic Induction

Watch
DannySmith420
Badges: 1
Rep:
?
#1
Report Thread starter 6 years ago
#1
Basically i am having trouble understanding electromagnetic induction and Lenz's Law. I am aware that when a magnet enters a conducting coil an is e.m.f induced proportional to flux linkage, and that a current carrying conductor has its own magnetic field - hence why when the current is induced in the coil a magnetic field is made around the coil to oppose the motion of the magnet and conserve the laws of energy. But the thing i dont understand is that current is only induced in a closed circuit, e.g a conducting rod will induce e.m.f but no current - if no current is induced in the conducter than it will not have its own magnetic field? And therefore where does the force come from what opposes it?
0
reply
mik1a
Badges: 10
Rep:
?
#2
Report 6 years ago
#2
The flux linkage is defined in terms of closed loops. The flux linkage describes the amount of magnetic flux that passes through a closed loop, and the EMF tells you the electric field induced around that loop (which will cause your current to circulate).

If you don't have a loop, you don't have a flux linkage, no flux linkage, no EMF, no current, no force!
0
reply
DannySmith420
Badges: 1
Rep:
?
#3
Report Thread starter 6 years ago
#3
(Original post by mik1a)
The flux linkage is defined in terms of closed loops. The flux linkage describes the amount of magnetic flux that passes through a closed loop, and the EMF tells you the electric field induced around that loop (which will cause your current to circulate).
If you don't have a loop, you don't have a flux linkage, no flux linkage, no EMF, no current, no force!
So is it not possible for an emf to be induced but no current is induced?
0
reply
mik1a
Badges: 10
Rep:
?
#4
Report 6 years ago
#4
The key requirement here for an EMF is a closed loop. As long as you have that, you will have an EMF. Now the closed loop might be made of some insulating material, so no current will flow. In this case you can have an EMF with no induced current (and therefore no force).

In the case of a straight length of wire or a pole, you don't have a closed loop, so no EMF.
0
reply
X

Quick Reply

Attached files
Write a reply...
Reply
new posts
Back
to top
Latest
My Feed

See more of what you like on
The Student Room

You can personalise what you see on TSR. Tell us a little about yourself to get started.

Personalise

Feeling behind at school/college? What is the best thing your teachers could to help you catch up?

Extra compulsory independent learning activities (eg, homework tasks) (3)
3.75%
Run extra compulsory lessons or workshops (11)
13.75%
Focus on making the normal lesson time with them as high quality as possible (14)
17.5%
Focus on making the normal learning resources as high quality/accessible as possible (9)
11.25%
Provide extra optional activities, lessons and/or workshops (29)
36.25%
Assess students, decide who needs extra support and focus on these students (14)
17.5%

Watched Threads

View All