Question

give reason for the following a magnetic needle get deflected when it is brought close to a current carrying conductor

Answer 1

HOLA friend!!
Rajdeep here....

When current flows through a conductor, two things happen:
1. Heat is formed
2. A magnetic field is formed.

Since magnetic field lines are formed, when a magnetic compass is kept under or over a conducting wire such that the north pole of the needle indicates the direction of current (or the south pole may indicate, there is no problem), there is a deflection in the magnetic needle.

Thanks!

Answer 2

This is because the current carring conductor develops a magnetic field and behaves like a magnet. Whereas the needle shows deflection because it is also a small magnet.