Advertisements
Advertisements
Question
What is an electromagnet?
Advertisements
Solution 1
The magnetic field produced due to the current flowing in a coil or a solenoid can be used to magnetize a material like soft iron temporarily. The insulated copper wire is wrapped on a soft iron piece. When current is passed through the coil using a battery and a key the iron piece behaves like a bar magnet as long as the current is being passed. Such a magnet is called an electromagnet.
Solution 2
An electromagnet is a temporary magnet which behaves as a magnet when electric current is passed through the insulated copper wire and loses its magnetism when current is stopped. It has a soft iron piece called the core with an insulated copper wire wound on it.

Notes
Student can refer to the provided solution based on their preferred question or marks.
APPEARS IN
RELATED QUESTIONS
State three ways in which the strength of an electromagnet can be increased.
State whether the following statement are true or false:
A motor works on the principle electric generator?
When the magnet shown in the diagram below is moving towards the coil, the galvanometer gives a reading to the right.
() What is the name of the effect being produced by the moving magnet?
(2) State what happens to the reading shown on the galvanometer when the magnet is moving away from the coil.
(3) The original experiment is repeated. This time the magnet is moved towards the coil at a great speed. State two changes you would notice in the reading on the galvanometer.
Name and state the law which determines the direction of induced current.
or
State Fleming’s right-hand rule.
Write Fleming’s right hand thumb rule with the help of diagram.
A straight metal wire crosses a magnetic field of flux 4 mWb in a time 0.4 s. Find the magnitude of the emf induced in the wire.
A cylindrical bar magnet is kept along the axis of a circular coil. If the magnet is rotated about its axis, then ____________.
We can induce the current in a coil by ____________.
The charge will flow through a galvanometer of resistance 200Ω connected to a 400Ω circular coil of 1000 turns wound on a wooden stick 20 mm in diameter, if a magnetic field B = 0.012 T parallel to the axis of the stick decreased suddenly to zero, is near ______.
