Two concentric circular loops P and Q lie in the same plane
PHYSICS · Single correct · A Level · Physics · Fields and their consequences · Fields and their consequences
Problem
Two concentric circular loops P and Q lie in the same plane. Loop P has radius 5cm and carries a 3A clockwise current. Loop Q has radius 10cm and carries a 3A anticlockwise current. Viewed from the same side, what is the direction of the net magnetic field at their common centre?
(a) Out of the page (towards the observer)
(b) Parallel to the plane of the loops
(c) Into the page (away from the observer)
(d) Net magnetic field is zero at the centre