# Pls explain Q.5

Due to current in A, direction of MF will be along the axis and towards right,

(a) Current in A will decrease and hence MF produced due to current in A at B will decrease.

So, according to lenz's law current in coil B will be such that it opposes the cause and produces MF in same direction as produced due to current in A.

By thumb rule current in resistor : a to b.

(b) The MF strength will increase at B due to current in A.

So, according to lenz's law current in coil B will be such that it opposes the cause and produces MF in opposite direction as produced due to current in A.

By thumb rule current in resistor : b to a.

(c) On decreasing R, currect passing through coil A will increase hence MF produced due to current in A at B will increase.

So, according to lenz's law current in coil B will be such that it opposes the cause and produces MF in opposite direction as produced due to current in A.

By thumb rule current in resistor : b to a.

Regards.

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