A beam of a $\alpha$ particles projected along the +x axis in a magnetic field experiences a force along the +y axis. The direction of the magnetic field would be:
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → Negative z axis
Since the force is in +y direction and the particle is moving along the +x direction, the magnetic field must be in +z direction for right hand rule to hold.