Physics- Wave Behaviour

Question 1

Name the 3 types of wave behaviour when a wave encounters an obstacle and the type of wave behaviour when a wave interacts with another wave.

Answer 1

Encounters an obstacle:
-Diffraction
-Reflection
-Refraction
Encounters another wave:
-Interference

Question 2

What is a Ripple tank?

Answer 2

A ripple tank is a shallow glass tank that can be used to show different concepts of wave behaviour in water waves.

Question 3

How are the waves created in a Ripple tank and what are the images made up of?

Answer 3

Waves are created using an oscillating dipper, and the images are projected below.
The images are made up of dark lines- wavefronts , which are the peaks of the waves viewed from above- the light spaces in between represent the troughs)

Question 4

Describe Reflection in waves:

Answer 4

Reflection occurs when a wave is ‘thrown back’ by a surface that cannot be penetrated.
Some infrared waves can be reflected by glass
Sound waves reflect off solid surfaces to form an echo

Question 5

How are echoes formed?

Answer 5

Echoes are formed when sound waves bounce off a surface and return to the listener, creating a repetition of the original sound.

Question 6

Describe Refraction in waves:

Answer 6

If a wave is able to penetrate into another substance, the wave can refract- the wave changes direction at the boundary as it travels at diff speeds in diff materials.

Question 7

Describe Diffraction in waves

Answer 7

Diffraction occurs when waves pass around a barrier- the waves redirect slightly to fill the ‘shadow zone’ (the space behind the barrier).
Radio waves can diffract around a mountain so the house receives a signal but microwaves (with shorter wavelengths) cannot.

Question 8

What has Diffraction taught us?

Answer 8

Diffraction of visible light waves has taught us more about the Universe and diffraction of X-rays can teach us more about crystal structures.

Question 9

Describe Interference in waves:

Answer 9

Interference is when two waves from separate sources come together, there is constructive interference (when two peaks /two troughs combine) and destructive interference (when a peak and a trough combine) - this is called the principle of superposition.