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.

Explanation

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`.