Question

Three identical long solenoids P,Q and R are connected to each other as shown in figure . If the magnetic field at the centre of P is 2.0 T, what would be the field at the centre of Q? Assume that the field due to any solenoid is confined within the volume of that solenoid only.

Answer 1

As the solenoids are identical, the currents in `Q` and `R` will be the same and will be half the current in `P`.The magnetic field within a solenoid is given by `B=mu_(0)ni`.Hence the field in `Q` will be equal to the field in `R` and will be half the field in `P` i.e., will be `2 T`.