PRACTICE COLLECTION / 55 PROBLEMS
Electricity & circuits
Build fields and simplify circuit connections. Each problem includes progressive hints, guided reasoning and a question to test the idea again. Problems marked “Free sample” are complete for everyone; membership opens the rest.
LEARN BEFORE YOU PRACTISE
Build the reasoning first.
Electric forces, fields and charge distributions
Use vectors, integration and symmetry to choose the right method for an electrostatic field.
10 worked examples · 9 checks →Electric potential and energy
Read a voltage map, track signed work and choose between fields and energy.
7 worked examples · 5 checks →Potential, capacitors and dipoles
Connect energy to field gradients, then track charge, voltage and mechanical constraints in electrostatic systems.
11 worked examples · 8 checks →Current, resistance and circuit constraints
Connect microscopic drift to wire geometry, circuit topology and temperature-dependent power.
11 worked examples · 7 checks →Kirchhoff networks and current direction
Read the connections, solve a shared voltage and audit the energy.
7 worked examples · 5 checks →Real sources, cell groups and useful power
Distinguish emf from terminal voltage, infer source models and track energy in both directions.
8 worked examples · 4 checks →RC switching: initial states, time constants and energy
Derive the exponential response and carry capacitor voltage correctly through a sequence of circuit changes.
6 worked examples · 6 checks →Electrical instruments: meter ranges and bridge balances
Design a shunt or multiplier, quantify loading and infer an unknown resistance from a reproducible null.
7 worked examples · 6 checks →Galvanometer half-deflection experiment
Use a controlled current split to measure coil resistance and current per scale division.
5 worked examples · 5 checks →CONCEPTS IN THIS COLLECTION
PRACTISE AT YOUR PACE
Problems in this collection
55 problems · Showing 12
Electricity & circuits
Calibrate what one division means
What is its figure of merit in μA per division?
Read graphs & measurementsElectricity & circuits
An electron transfer changes a signed integer count
What is its final charge?
Apply a principleElectricity & circuits
A field arrow has a direction as well as a size
What is the signed y component of the electric field at P?
Connect conceptsElectricity & circuits
A long route between equal potentials
What is the total work done by the electrostatic field?
Compare casesElectricity & circuits
Move within an empty conducting shell
In the test-charge limit, what is the source potential at the centre?
Compare casesElectricity & circuits
Do the electric fields cancel at the midpoint?
What is the electric field at the midpoint?
Connect conceptsElectricity & circuits
Half the pointer, a changing source current
The shunt-equals-coil shortcut is a limiting result, not the defining physics of half deflection.
Apply a principleElectricity & circuits
A neutral pair can still require work to turn
What work must an external agent supply?
Apply a principleElectricity & circuits
Higher potential can mean lower energy
What work is done by the electric field?
Apply a principleElectricity & circuits
Opposite particle motion can add current
What is the conventional current to the right?
Connect conceptsElectricity & circuits
Energy gained by a negative probe
What is its final kinetic energy?
Apply a principleElectricity & circuits
Read field from labelled voltage contours
What is the field magnitude?
Read graphs & measurements12 of 55 shown