A proton moves north at $10^6$ m/s in a magnetic field of $0.1$ T poin…

Question

A proton moves north at $10^6$ m/s in a magnetic field of $0.1$ T pointing east. The magnetic force on it is:

Accepted Answer

C. $1.6	imes 10^{-14}$ N upward, by right-hand rule for the cross

$F = qvB\sin 90 = 1.6	imes 10^{-19}\cdot 10^6\cdot 0.1 = 1.6	imes 10^{-14}$ N; direction upward by right-hand rule.

Answer

Zero, since proton velocity is along the field direction here

Answer

$1.6	imes 10^{-14}$ N along east, in the field direction itself

Answer

$1.6	imes 10^{-12}$ N downward, larger by a factor of hundred