Question

When a magnetic compass needle is carried nearby to a straight wire carrying current, then
(I) the straight wire cause a noticeable deflection in the compass needle
(II) the alignment of the needle is tangential to an imaginary circle with straight wire as its centre and has a plane perpendicular to the wire

• A. (I) is correct
• B. (II) is correct
• C. both (I) and (II) are correct
• D. neither (I) nor (II) is correct

Answer 1

Answer: (C)

Both points are correct and these are the result of experiments done by Danish physicist Hans Christian Oersted in $1820$