An electromagnet used in a school laboratory consists of a soft iron core tightly…
PHYSICS · Multi-part · CBSE · Physics · Magnetic Effects of Electric Current · Magnetic Effects of Electric Current
Problem
An electromagnet used in a school laboratory consists of a soft iron core tightly wound with insulated copper wire.
(a) State two reasons why soft iron is preferred to steel for the core of an electromagnet used for temporary lifting work.
(b) List any three factors that determine the strength of the magnetic field produced inside the core when a given current is passed.
(c) If the laboratory technician replaces the existing winding by another coil having twice as many turns per unit length but keeps the current the same, predict qualitatively how the lifting power of the electromagnet will change. Give reasons for your answer.