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
It is desired to measure the magnitude of field between the poles of a powerful loud speaker magnet. A small flat search coil of area 2 cm2 with 25 closely wound turns, is positioned normal to the field direction, and then quickly snatched out of the field region. Equivalently, one can give it a quick 90° turn to bring its plane parallel to the field direction. The total charge flown in the coil (measured by a ballistic galvanometer connected to coil) is 7.5 mC. The combined resistance of the coil and the galvanometer is 0.50 Ω. Estimate the field strength of magnet.
What do you understand by the term "electromagnetic induction"? Explain with the help of a diagram.
Why soft iron is preferred to be used as the core of the electromagnet of an electric bell?
Observe the given figure of Fleming’s Right Hand Rule and write the labels of A and B correctly.

A thin semi-circular conducting ring (PQR) of radius r is falling with its plane vertical in a horizontal magnetic field B, as shown in the figure.

The potential difference developed across the ring when its speed v , is
Establish the fact that the relative motion between the coil and the magnet induces an emf in the coil of a closed circuit.
Metal rings P and Q are lying in the same plane, where current I is increasing steadily. The induced current in metal rings is shown correctly in figure.

What should be the core of an electromagnet?
Show that for a given positive ion species in a cyclotron, (i) the radius of their circular path inside a dee is directly proportional to their speed, and (ii) the maximum ion energy achievable is directly proportional to the square of the magnetic induction.
