The strength of an electromagnet can be altered by

A. using AC current.

B. increasing the number of coils around the core.

C. increasing the diameter of the wire wrapped around the core.

D. using DC current.

The strength of an electromagnet can be altered by increasing the number of coils around the core. The more times the coil is wrapped, the stronger the electromagnet is.

Your answer is: B) Increasing the number of coils around the core

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