Advertisements
Advertisements
प्रश्न
Why is soft iron generally used as the core of the electromagnet?
Advertisements
उत्तर
(i) Soft iron has less retentivity so it acquires the magnetic properties only when the current flows through the coil wound on it and loses the magnetic properties as the current is switched off.
(ii) The soft iron intensifies the magnetic field of the electromagnet because of its high permeability.
APPEARS IN
संबंधित प्रश्न
Name and state the rule by which polarity at the ends of a current carrying solenoid is determined.
The magnetic flux through a coil having 100 turns decreases from 5 milli weber to zero in 5 second. Calculate the e.m.f. induced in the coil.
What is an electromagnet?
State the condition when an electric charge can give rise to a magnetic field.
What will be the effect on the working of an electric bell if instead of a direct current an alternating current is used?
State three factors which govern the speed of rotation of an electric motor.
State the energy change that takes’place in a D. C. motor.
What is dynomo (a.c. generator)? State the principle on which it works.
Point out three differences between an electromagnet and a bar (or permanent) magnet.
Which magnet will you use?
Iron is to be separated from trash.
