How many questions are in this quiz?

This quiz has 108 questions on magnetic forces acting on moving charges and currents.

Is there a timer or speed requirement?

No. The quiz has no timer, so you can take your time to apply the right-hand rule and check signs.

What answer format does the quiz use?

Each question is multiple-choice with 4 options, designed for quick concept checks and short calculations.

How do I choose the number of questions and difficulty?

Use the start settings to select your preferred question count and a difficulty level; the overall pool is mixed.

What topics are covered besides F = q(v × B)?

You’ll see direction reasoning, angle dependence, circular/helical motion in uniform fields, and common sign/geometry traps.

Magnetic Forces on Moving Charges Quiz

About this quiz

What you’ll practice

Build confidence with the Lorentz force F = q(v × B), including how charge sign flips direction and how speed and field strength affect magnitude. You’ll also connect particle motion (helical/circular paths) to real setups like velocity selectors and magnetic bending.

Expect a balanced mix of conceptual checks and light math: units, proportional reasoning, and right-hand-rule direction choices. The quiz uses 4 options per question and no timer, so you can slow down and verify your reasoning.

Common pitfalls to avoid

Mixing up v × B direction, forgetting the sign of q, or assuming the force is along the field are the most frequent errors. Another trap is using sin/cos incorrectly when velocity is not perpendicular to the magnetic field.

How difficulty and length work

Difficulty is mixed by design: easier items reinforce core rules, while harder ones combine geometry, components, and motion relationships. Before you start, pick your question count and a difficulty setting to tailor the session—short for review, longer for full coverage.

Quick tips for better scores

Use the right-hand rule for v × B first, then reverse if the charge is negative
Remember: magnetic force is perpendicular to velocity, so it changes direction more than speed
For angles, use |F| = |q|vB sin(θ) and check whether θ is between v and B
In uniform B with v ⟂ B, motion is circular; with a parallel component, it becomes helical
Track units: tesla (T), coulomb (C), m/s, and newton (N)
When stuck, test each option against direction and proportionality (double v → double F)