Test your knowledge with free interactive questions on Seneca — used by over 10 million students.

Resistance

Resistance is a measure of how difficult it is for current to flow through a component.

Charge flow

Charge flow

  • When charge flows in an electric circuit, the size of the current is affected by two things:
    1. The resistance: If the resistance is increased, the current will decrease.
    2. The potential difference: If the potential difference is increased the current will increase.
Units - Ohms

Units - Ohms

  • Resistance is measured in ohms, Ω.

Measuring Resistance

We calculate the resistance using R = Δ V/I. We calculate potential difference using a voltmeter and current using an ammeter at the same time.

Potential difference across a component

Potential difference across a component

  • To measure the resistance of a component (e.g. lamp or resistor), measure the potential difference across the component.
Diagram
Current through a component

Current through a component

  • Use an ammeter to measure the current flowing through a component.
Diagram
Resistance

Resistance

  • The longer the wire, the higher the resistance.
Jump to other topics
1

Space, Time & Motion

2

The Particulate Nature of Matter

3

Wave Behaviour

4

Fields

4.1

Circular Motion

4.2

Newton's Law of Gravitation

4.3

Fields

4.4

Fields at Work

4.5

Electric Fields

4.6

Magnetic Effect of Electric Currents

4.7

Heating Effect of Currents

4.8

Electromagnetic Induction

4.9

Power Generation & Transmission

4.10

Capacitance

5

Nuclear & Quantum Physics

6

Measurements

Practice questions on Resistance

Can you answer these? Test yourself with free interactive practice on Seneca — used by over 10 million students.

  1. 1
  2. 2
  3. 3
  4. 4
  5. 5
Answer all questions on Resistance

Unlock your full potential with Seneca Premium

  • Unlimited access to 10,000+ open-ended exam questions

  • Mini-mock exams based on your study history

  • Unlock 800+ premium courses & e-books

Get started with Seneca Premium