A proton and electron, each travelling with the same velocity, enter a region of uniform magnetic field. They experience
A) forces in the same direction and having ratio $\mathrm{F}_{\mathrm{p}} / \mathrm{F}_{\mathrm{e}}=\mathrm{m}_{\mathrm{e}} / \mathrm{m}_{\mathrm{p}}$.
B) the same force.
C) forces equal in magnitude, but opposite in direction.
D) forces opposite in direction and having ratio $\mathrm{F}_{\mathrm{p}} / \mathrm{F}_{\mathrm{e}}=\mathrm{m}_{\mathrm{e}} / \mathrm{m}_{\mathrm{p}}$.

Question

Quizplus · Accepted Answer

The force on a charged particle in a magnetic field is given by $F = qvB\sin(\theta)$, where $q$ is the charge, $v$ is the velocity, $B$ is the magnetic field strength, and $\theta$ is the angle between the velocity and the magnetic field. Since the proton and electron have equal and opposite charges and are moving with the same velocity, they experience forces of equal magnitude but in opposite directions due to their opposite charges.

A Proton and Electron, Each Travelling with the Same Velocity Fp/Fe=me/mp\mathrm{F}_{\mathrm{p}} / \mathrm{F}_{\mathrm{e}}=\mathrm{m}_{\mathrm{e}} / \mathrm{m}_{\mathrm{p}}Fp​/Fe​=me​/mp​

A Proton and Electron, Each Travelling with the Same Velocity $\mathrm{F}_{\mathrm{p}} / \mathrm{F}_{\mathrm{e}}=\mathrm{m}_{\mathrm{e}} / \mathrm{m}_{\mathrm{p}}$