Edexcel GCSE Combined Science Physics 1SC0
Key Concepts of Physics
Motion and Forces
Conservation of Energy
Waves
Light and the Electromagnetic Spectrum
Radioactivity
Energy – Forces Doing Work
Forces and Their Effects
Electricity and Circuits
Magnetism and the Motor Effect
Electromagnetic Induction
Particle Model
Electricity and Circuits
Potential difference and the voltmeter
- 3 things to know
- Paper 6
Overview
How a voltmeter is connected and what it reads, why its resistance is very high, potential difference as energy per coulomb, and why one volt is one joule per coulomb.
What you need to know
Answer each one before you reveal it.
What unit does a voltmeter read in?
Why is a voltmeter built to have a very high resistance?
Questions from this subtopic
Each one with the model answer underneath.
- 1
How must a voltmeter be connected to measure the potential difference across a resistor?
Model answer
The voltmeter is connected in parallel with the resistor, across its two ends.
- 2
What unit does a voltmeter read in?
Model answer
A voltmeter reads potential difference in volts, symbol V.
- 3
Why is a voltmeter built to have a very high resistance?
Model answer
A very high resistance means almost no current passes through the voltmeter, so it barely changes the circuit it is measuring.
- 4
What does a voltmeter connected across a lamp tell you about that lamp?
Model answer
It gives the potential difference across the lamp, which is the energy transferred by each coulomb passing through it.
- 5
What happens if a voltmeter is wrongly connected in series with a lamp?
Model answer
Its very high resistance cuts the current to almost nothing, so the lamp does not light.
- 6
What is meant by the potential difference between two points in a circuit?
Model answer
It is the energy transferred per coulomb of charge that moves between those two points.
Other ways to work this
The same content, four other ways.
What is inside Levo
Six ways to work the same material.
Every question in Electricity and Circuits, on a schedule.
Attempt a question from memory, write the correct version, then attempt it again. Levo records the jump between your first attempt and your last, and brings each question back on the day you are due to forget it.
Or £46 a year, about £3.83 a month. Cancel anytime.