Magnetic fields quiz, Physics grades 11-12 (free)

Quick answer: A magnetic field exerts a force on moving charges and on current-carrying wires. This Physics 11-12 quiz checks magnetic fields with 10 multiple-choice questions and instant feedback; every answer comes with a short explanation.

Magnetic fields quiz for A Level physics: 10 questions with answers

This magnetic fields quiz for physics grades 11-12 has quick multiple-choice questions with instant feedback. Need a refresher first? Read the lesson or do the worksheet on magnetic fields.

Ten quick questions on magnetic forces, circular paths and velocity selectors. Choose the best answer. Each explanation points out the mistake that the wrong options are built on.

Level: Physics grades 11-12 (A Level · IB · Class 11-12) · Curriculum: IB D.3

Contents

Magnetic fields quiz: the questions

Which unit equals one newton per ampere per metre?

A straight wire lies along the field lines of a uniform magnet. The magnetic force on it is

Which quantity does a magnetic force on a moving charge change?

Which expression gives the radius of a charge's circular path?

A proton moves at twice the speed in the same field. What happens to the period?

In a velocity selector, which speed passes undeflected?

An electron moves along the direction of the field. The force on it is

Doubling the current in a wire in a fixed field makes the force

A charge enters a field at an angle to the lines. Its path is a

Why does the magnetic force do no work on a moving charge?

Unit of magnetic flux density — tesla (T) = N A⁻¹ m⁻¹

Force on a wire — F = BIL sin θ

Force on a moving charge — F = Bqv sin θ

Radius of orbit — r = mv/(qB)

Period of orbit — T = 2πm/(qB)

Velocity selector speed — v = E/B

Work done by a magnetic force — zero; speed constant

Force when v is parallel to B — zero

Direction rule for force on wire — Fleming's left-hand rule

What a negative charge does to the force — reverses its direction

Magnetic fields quiz for A Level physics: 10 questions with answers

Magnetic fields quiz: the questions