Question

The figure shows three long straight wires P. Q and R carrying currents normal to the plane of the paper. All three currents have the same magnitude. Which arrow best shows the direction of the resultant force on the wire P

• A. A
• B. B
• C. C
• D. D

Answer 1

The correct option is C C

Now from P-Q:

Currents are in opposite drection. So force will be repulsive and will be along B.

Now from P-R:

Currents are in same direction. So, force will be attractove and will be along D.

So, the direction of net force by considering the vector resultant force will be along C.