Question

Assertion: A soft iron core is used in a moving coil galvanometer to increase the strength of magnetic field
Reason: From soft iron more number of the magnetic lines of force passes

• A. Both A and R are true and R is the correct explanation of A
• B. Both A and R are true and R is not correct explanation of A
• C. A is true, but R is false
• D. A is false, but R is true

Answer 1

The correct option is A Both A and R are true and R is the correct explanation of A

Iron is said to be magnetically soft, it can be very easily magnetized, even in a weak field. As soon as the field is removed, the magnetism is lost but magnetically soft materials behaves like temporary magnets. Hence, in moving coil galvanometer, to increase the strength of magnetic field a soft iron core is used since, soft iron allows passage of magnetic lines of force.