Advertisements
Advertisements
Question
Write the answer in your word.
How is an electromagnet made?
Advertisements
Solution
For the construction of an electromagnet, we require an iron nail, a long insulated copper wire, a battery and a switch.
The long, insulated copper wire is first wound on the iron nail. Then the two free ends of the wire are connected to the battery and the switch as shown. Now that the switch is turned on, current flows through the circuit. Due to this flow of current, the insulated copper wire and iron nail act as an electromagnet. Now, if iron pins are brought close to this set-up, they stick to the iron nail.
As soon as the current stops flowing in the circuit, the iron nail loses magnetism and the pins fall off.
Case: Switch open
Case: Switch close
RELATED QUESTIONS
State two ways of magnetising an iron piece?
You are given an iron nail, a torch cell, and a long piece of insulated copper wire. With the help of a labelled neat diagram, describe in steps how you will make the nail, an electromagnet.
Name the material used for making the armature of an electric bell. Give a reason for your answer.
State two factors on which the magnitude of an induced e.m.f. in the secondary coils of a transformer depends.
What is a permanent magnet? Give one use of it.
What will be the effect on the working of an electric bell if instead of a direct current an alternating current is used?
State the position of armature coil relative to the direction of magnetic field, in a D. C. motor when the deflecting couple acting an the coil is maximum.
What are the factors that govern the magnitude of force acting on a current carrying conductor which is freely suspended in a magnetic field?
Point out three differences between an electromagnet and a bar (or permanent) magnet.
State the function of a split ring in D.C. motor.
