Q.

A wire carrying a current I along the positive x-axis has length L. It is kept in a magnetic field B=(2i^+3j^-4k^)T. The magnitude of the magnetic force acting on the wire is  [2023]
 

1 5IL  
2 3IL  
3 3IL  
4 5IL  

Ans.

(1)

Given  B=(2i^+3j^-4k^)T

F=IL×B=ILi^×(2i^+3j^-4k^)  ;  F=3ILk^+4ILj^  ;  F=5IL