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Question

A charged particle a moves with velocity v in a magnetic field B that perpendicular to each other.The particle experiences Lorentz Force of F.If another particle of 4q moves twice faster in similar field,then how strong of Lorentz force is the second particle experienced?

A.2
B.4
C.6
D.8
E.10

Answer 1

F=qvXB. Since the field is already perpendicular to the velocity, the formula is just qvb. If the charge quadruples and the speed doubles, the force will be 8 times as great (4q*2v*B=8qvb)