Answer:
4.49 x 10^-11 newton
Step-by-step explanation:
v = 12.3 m/s along north = 12.3 j m/s
B = 4.78 x 10^-5 T downwards = 4.78 x 10^-5 k T
q = 7.64 x 10^-8 C
force on a charged particle when it is moving in a uniform magnetic field is given by
F = q (v x B )
F = 7.64 x 10^-8 {(12.3 i) x (4.78 x 10^-5 k)}
F = 4.49 x 10^-11 (- k) newton
magnitude of force = 4.49 x 10^-11 newton