HOW DOES THE MUTUAL INDUCTANCE OF A PAIR OF COIL CHANGE WHEN

1 THE DISTANCE B/W 2 COIL IS INCREASED

2 NUMBER OF TURNS IN EACH OF 2 COIL IS DECREASED 

1. on increasing the distance between the coil due to the magnetic flux linked with secondary coil due to current flowing through the primary coil will decrease .hence mutual inductance of the coil will decrease .
2. Mutual induction of two coils,

M=mew ₀n₁n₂Al

• obvously th mutual inductance of two coils will decrease on decreasing the no. of turns