A closed loop `PQRS` carrying a current is place in a unifrom magnetic forces on segments `PS, SR` and `RQ` are `F_(1), F_(2)` and `F_(3)` respectively and are in the plane of the paper and along the directions shown, the force on the segment `QP` is

Options

A. `sqrt((F_(3) - F_(1))^(2) - F_(2)^(2))`
B. `F_(3) + F_(1) - F_(2)`
C. `F_(3) - F_(1) + F_(2)`
D. `sqrt((F_(3) - F_(1))^(2) + F_(2)^(2))`

Answer

D

Explanation

Net magnetic force on loop is zero.
Force on `PQ` is equal and opposite of resultant of `F_(1)`,
`F_(3)` and `F_(2)` i.e. `sqrt((F_(3) - F_(1))^(2) + F_(2)^(2))`