Which of the following can change when a proton moves freely in a magnetic field?

Subject: General Science

Topic: Magnetic Effects of Electric Current

Options:

1. Option A: Mass
2. Option B: Speed
3. Option C: Velocity
4. Option D: Both B and C

Correct Answer:

Option D: Both B and C

Explanation:

A magnetic field can change the direction of motion of a charged particle (velocity), but not its speed or mass. Since velocity changes, momentum (mass × velocity) also changes.