I'm not so sure what this question is even asking. If there is a magnetic field from a source at the origin, and you place a ring around it, wouldn't the overall magnetic force due to that source be 0?
mag force will only be 0 when it is acting along radius.
It wont in the case i told you and neither if source is at origin!!!
in your case ... field perpendicular to the plane of loop will give 0 force but there still will be a field along radius!!!!
Hey hang on ... it got it!!!!
your question gave me the answer!!!!!!!!!!!!!!
the field left along radius in your case will give force and thats the answer!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Thanks for the question !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! :tongue2: