A student places a small magnetic compass directly below a long
PHYSICS · Multi-part · CBSE · Physics · Magnetic Effects of Electric Current · Magnetic Effects of Electric Current
Problem
A student places a small magnetic compass directly below a long, straight, horizontal conductor that is connected to a battery through a key.
(i) Explain what happens to the compass needle immediately after the key is pressed to complete the circuit.
(ii) Describe the change in compass deflection when the terminals of the battery are interchanged.
(iii) Give a reason for the compass needle returning to its original north–south direction a few moments after the key is released.