Which of these possibilities will produce emf

[songoku]

Homework Statement

Which one will produce e.m.f?
(i) A circular coil placed in a non-homogenous magnetic field
(ii) A circular coil moved with constant velocity in a homogenous magnetic field
(iii) A circular coil moved with constant velocity in a non-homogenous magnetic field
(iv) None of the above

Homework Equations

E=-N\frac{d\phi}{dt}

\phi=BA~\cos \theta

The Attempt at a Solution

I think the answer can be (i) and (iii) because there is change in B and it will cause the change in magnetic flux. Am I right?

 

[rl.bhat]

Non-homogeneous field may not change with time. It changes with distance. So by keeping the coil in such field will not produce EMF.

 

[songoku]

Hi Mr rl.bhat

I don't really understand about the field "changing with distance". Maybe it means, for example, the first 2 m the field is 2 T, then for the next 5 m the field is 10 T?

 

[rl.bhat]

Hi Mr rl.bhat

I don't really understand about the field "changing with distance". Maybe it means, for example, the first 2 m the field is 2 T, then for the next 5 m the field is 10 T?

According to me, the diverging or converging magnetic field can be treated as non-homogeneous field.

 

[songoku]

Hi Mr. rl.bhat

Now I don't understand the term "converging and diverging magnetic field"...

 

[songoku]

hi Mr. rl.bhat

Non-homogeneous field may not change with time. It changes with distance. So by keeping the coil in such field will not produce EMF.

I have another opinion. Since the field changes with distance (although I don't know what this means) and the distance changes with time, it implies that the field changes with time. Therefore, e.m.f will be produced ?

 

[rl.bhat]

If you consider field due to current carrying solenoid, depending on the direction of the current, the magnetic field from one end is diverging and on the other end it is converging.
If you keep a coil at rest any where near the solenoid, emf will not be induced.
I don't know what is interpretation of homogeneous and non homogeneous field.