Question

Magnetic effect of current was discovered by
A. Faraday
B. Oersted
C. Ampere
D. Joule

Answer 1

Hint: Similar to other effects electric current also produces magnetic effect. The magnetic effect of electric current is called the electromagnetic effect. It is observed that when a compass is brought near a current carrying wire, the needle of the compass gets deflected because of the flow of electricity. This shows that electric current produces a magnetic effect.

Complete step by step answer:
-Hans Christian was a Danish physicist and chemist that discovered that electric current creates magnetic fields which was the first relation found between electricity and magnetism.
-The magnetic effect due to a current carrying wire was discovered by Hans Christian Oersted in 1820. He manifested the effect by placing a compass near to a long straight wire which is carrying current and noting down its deflection. When the direction of the current was reversed, the compass needle get deflected towards the opposite direction.
-He observed that flow of electric current through a wire produces a magnetic field around it. The magnetic effect of current can be manifested by the following experiment.First, make a simple electric circuit by joining a long straight wire with a battery and a plug. Now, take a magnetic compass and place the straight wire parallel and over the compass needle. Then switch on the circuit so that current flows through the wire from south to north direction. Now, you will find out that the north pole of the compass needle gets deflected towards the west.

Therefore, option (B) is correct.

Note: The direction of deflection of the magnetic needle can be amiably figured out by using the SNOW rule. According to the SNOW rule, when a current flows through a conductor from South to North direction and the wire is held over a magnetic needle then the north pole of the magnetic needle deflects towards west.