समान संवेग वाले आयनित हाइड्रोजन परमाणु और α-कण एक नियत चुंबकीय क्षेत्र B के लंबवत प्रवेश करते हैं। उनके पथों की त्रिज्याओं का अनुपात rH ∶ rα होगा:

Which of the following is an application of the magnetic effect of electric current?

Two wires 2 mm apart supply current to a 100 V, 1 kW heater. The force per metre between the wires is (Take μ0 = 4π × 10-7 T·m/A):

A straight wire is kept horizontally along the east-west direction. If a steady current flows in the wire from east to west, the magnetic field at a point directly above the wire will point towards the: