Force on moving charge
A charge of \(0.003\,\text{C}\) moves at \(70\,\text{m s}^{-1}\) perpendicular to a \(0.4\,\text{T}\) magnetic field in a charged-particle beam tube. Calculate the magnetic force. Use the diagram labels before calculating the requested value. Enter the numerical result and choose the interpretation that matches the field physics.
Worked practice: physics data and result
Read the physical quantities first, then calculate the result and state what it means.
Write a full answer
Now write the response in full, in your own words — this is what the exam asks for. The AI marks it on the same moves you built above (focus, evidence, technique, judgement) and gives feedback on reasoning, evidence, and expression.