Wave Basics
Waves transfer energy without transferring matter.
About this topic
A wave is a disturbance that transfers energy from place to place without transferring matter. Key quantities: amplitude (maximum displacement), wavelength λ (distance between successive crests), frequency f (cycles per second) and wave speed v = fλ.
Mechanical waves, such as sound and water waves, need a medium to travel through, whereas electromagnetic waves, such as light, can cross a vacuum. Each particle in the medium simply oscillates about its place while the pattern moves on. Waves can be reflected, refracted, diffracted and can interfere, behaviours that help identify something as a wave.
Worked example: a water wave with a wavelength of 2 m and frequency of 0.5 Hz travels at v = 0.5 × 2 = 1 m/s. If a cork floating on the sea bobs up and down but stays roughly in place as waves pass, you can see the wave moves but the water does not travel with it.
Waves carry the energy in sound, light, earthquakes, radio and the ocean. Doubling the amplitude of a wave quadruples its energy. A common mistake is to confuse amplitude with wavelength, or to think a faster wave means a higher frequency; in a given medium the speed is fixed, so higher frequency gives a shorter wavelength.
Key ideas
- Wavelength, frequency, amplitude
- v = fλ
- Transverse vs longitudinal
Quick check
Use cases: where Wave Basics helps
- Homework: review the key idea behind Wave Basics before you start a problem set.
- Exam revision: use the quick check to test whether you can recall Wave Basics without notes.
- Visual learning: play with the interactive lab to see how Wave Basics changes when you adjust its inputs.
- Teaching a friend: explain Wave Basics in your own words, then compare your version with the key ideas.
The same laws describe car crashes, sports, satellites and everyday machines.
Frequently asked questions
What is Wave Basics?
Waves transfer energy without transferring matter.
What will I learn in Wave Basics?
Wavelength, frequency, amplitude. v = fλ. Transverse vs longitudinal.
Is Wave Basics part of Physics?
Yes. It is one of 150 Physics topics on LearnViz HighSchoolEdu, with 3 key ideas, a live animation and a quick check.
Does the Wave Basics lab work on a phone or tablet?
Yes. The animation resizes to fit your screen and supports touch, so you can drag, tap and slide with your finger.
How should I study Wave Basics?
Read the summary and key ideas first, play with the interactive lab to see the idea in motion, then answer the quick check. If you get a question wrong, go back to the key idea it tests.
Do I need an account, and is my progress saved?
No account is needed. Marking a topic as learned is saved in your own browser, so it stays on that device and is not sent to a server.