Question

A circular metal loop is kept entirely within a magnetic field, but moved to a region of higher field strength while not rotated. What could you do to its diameter to prevent an induced current in it? Explain.

Answer 1

The Answer:

The diameter will be reduced or shorten to prevent the induced current in the metal loop

explanation:

Magnetic flux is given as

Φ = BA•Cosθ

Since the angle is kept constant.

So to have same magnetic flux with larger magnetic field required only the diameter to changed

From the equation above,

Φ = BA•Cosθ

B= Φ / A•Cosθ

Since both Flux and the angle is constant

Then, The magnetic field is inversely proportional to the Area

And the areas is a function of diameter, Area = πd²/4

So to have a larger magnetic field, we need to reduce or shorten the diameter.

As d reduces, B increases.