Question:
Charges Q1 > 0 and Q2 < 0 have velocities in the plane of the page. A uniform magnetic field with magnitude B is going into the plane of the page, and a uniform electric field with magnitude E is going up (towards the top of the page).
I the speed of charge 1 satisfies v1 > E/B and the speed of charge 2 satisfies v2 < E/B, what is the direction of the net force on charges 1 and 2? (Up means towards the top of the page, and down means toward the bottom of the page.)
Calculate Direction Of Net Force On Charges With Velocities