Discussion Forum



1)

The direction of magnetic field dB due to current element dl at a distance r is the  direction of 


A) r x dl

B) dl x r

C) (rdl) r

D) dl

Answer:

Option B

Explanation:

 The direction of dB is the direction of vector dl x r From right-hand screw rule if we place a right-handed screw at the point where the magnetic field is needed to be determined and turn its handle from dl to r. then the direction in which the  screw advances gives the direction of field dB