Why is a large value of mutual inductance is not always desirable and how can it be minimised ?

 Mutual inductance is a common phenomenon associated with transformer.A large value of mutual inductance is desirable for a transformer but higher mutual inductance is not desirable for home appliances such as an electric clothes dryer.

A dangerous emf can be induced on the metallic case of the dryer if the mutual inductance between its heating coils and the case is large.

ln order to minimise its value, the heating coils are counter wound so that their magnetic fields cancel one another & reduces the mutual inductance with the case of the dryer.