physicsRP4 · ElectricityPaper 1Combined and Separate

I–V characteristics

Method overview

Construct circuit with ammeter in series, voltmeter across component and variable resistor. Vary potential difference, record V and I in both directions where appropriate, and plot I against V.

Apparatus set-up

Diagram

DC supply; ammeter; voltmeter; variable resistor; fixed resistor; lamp; diode; switch

Independent variable

potential difference including polarity

Dependent variable

current

Control variables

component; temperature control where required; circuit; reading intervals

Apparatus

DC supply; ammeter; voltmeter; variable resistor; fixed resistor; lamp; diode; switch

Safety

Use low voltage; lamp becomes hot; switch off before changing components/polarity.

Scientific rationale

Variable resistor controls current; reversing supply reveals diode direction; lamp heating raises resistance.

You will work through 12 questions across four layers — Core, Deepen, Exam and Transfer Challenge. Hints reveal in two stages, and the model answer only appears once you ask for it. Mark yourself honestly at each question so your mastery-by-skill breakdown stays accurate.