Question

A charge $+Q$ is moving upwards vertically. It enters a magnetic field directed to north. The force on the charge will be towards

• A. east
• B. west
• C. north
• D. south

Answer 1

Answer: (B)

A positive charge is moving vertically upwards.when it enters a region of magnetic field directed towards north, what is the direction of the force on charge. Using this $[\overrightarrow{F}=q(\overrightarrow{v}\times \overrightarrow{B})]$ equation, and right hand rule, we find that the force acts in West direction.