Rankers Physics

Magnetic Properties of Matter: Practice Problem & Solution

29. Electromagnets are made of soft iron because soft iron has: (2010 Pre)
High retentivity and low coercive force
Low retentivity and high coercive force
High retentivity and high coercive force
Low retentivity and low coercive force

Short Solution (Best for NEET):

To solve this problem, we apply the core principles of Magnetic Properties of Matter. Understanding the underlying formula is key to arriving at the correct answer below:

An electromagnet should easily magnetize when current is switched on and readily lose its magnetism when current is turned off. Thus, the material must have low retentivity and low coercivity.

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