Physics (P1) - Waves

?
  • Created by: Roma
  • Created on: 13-12-13 20:39
What are waves used for?
To transfer energy and information.
1 of 38
How do transverse waves tavel?
The oscillation (vibration) of the particles is perpendicular (at right angles) to the direction in which the wave travels.
2 of 38
How do longitudinal waves tavel?
The oscillation (vibration) of the particles is parallel to the direction of the wave. They have compressions and rarefactions.
3 of 38
What are electromagnetic waves and give examples of them?
Transverse waves that can travel through a vacuum due to having no moving particles as they are in electric and magnetic fields. E.g. light and radio waves.
4 of 38
What are mechanical waves and give an example of one?
Transverse of longitudinal waves that travel through a substance. E.g. sound waves (longitudinal).
5 of 38
What is the amplitude of a wave?
The height of the wave crest or the depth of the wave trough from rest position.
6 of 38
What is the wavelength of a wave?
Transverse - the distance from crest to crest or trough to wave . Longitudinal - the distance from the middle of one rarefaction to the next, or the middle of one compression to the next.
7 of 38
What is the frequency (hertz) of a wave?
The number of wave crests/compressions passing a point in one second.
8 of 38
What is the incident ray?
The ray that goes towards the mirror.
9 of 38
What is the reflected ray?
The ray is coming away from the mirror.
10 of 38
What is the normal?
A line perpendicular to the mirror at the point where the incident ray hits the mirror.
11 of 38
What is the angle of incidence?
The angle between the incident ray and the normal.
12 of 38
What is the angle of reflection?
The angle between the reflected ray and the normal.
13 of 38
What is the relation between the angle of incidence and the angle of reflection?
They are equal.
14 of 38
What is the image in a plane mirror?
The same size as the original object, upright, the same distance behind the mirror as the original object, virtual.
15 of 38
What is a real image?
One that can be formed on a screen, because the rays of light that produce the image actually pass through it.
16 of 38
What is a virtual image?
One that cannot be formed on a screen, because the rays of light that produce the image, do not actually pass through it.
17 of 38
What do waves do when the cross a boundary between different substances?
They change speed, the wavelength change, but the frequency stays the same.
18 of 38
What is refraction?
The change of direction of all waves (inc. light and sound) when it crosses a boundary between two substances.
19 of 38
What does change in speed of waves cause?
A change in direction of the waves.
20 of 38
What happens when light enters a more dense substance?
It slows down and the ray changes direction towards the normal.
21 of 38
What happens when light enters a less dense substance?
It speeds up and the ray changes direction away from the normal.
22 of 38
What happens if a light ray travelling along the normal crosses a boundary between different substances?
It will not change direction.
23 of 38
What is dispersion?
When a ray of white light is shone onto a triangular glass prism and we can see the spectrum being produced, because different colours of light have different wavelengths are are refracted by slightly different amounts.
24 of 38
Which colours are refracted the most and the least?
Violet is refracted the most, and red the least.
25 of 38
What is diffraction?
The spreading out of waves (inc. light and sound) when they pass through a gap or round the edge of an obstacle.
26 of 38
When is diffraction most noticeable/greater?
The wavelength is the same size as the gap or the obstacle/the gap is narrow.
27 of 38
Why might people receive bad TV signal?
It the radio waves don't diffract enough when they go over hills.
28 of 38
What are sound waves?
Longitudinal waves caused by mechanical vibrations in a substance. They can travel through all three states of matter (fastest in solids and slowest in gases), but cannot travel through a vacuum.
29 of 38
How can you test that sound waves cannot travel through a vacuum?
Listening to a ringing bell in a bell jar, and as the air is pumped out, the sound fades away.
30 of 38
What range of frequencies can be heard by humans?
20Hz - 20 000Hz.
31 of 38
What is the reflection of sound waves?
Echoes.
32 of 38
What conditions are best for echoes?
Hard, flat surface, as soft things will absorb the sound instead of reflecting it.
33 of 38
What else can sound do apart from reflect?
They can be refracted at the boundaries between layers of air at different temperatures, and also diffracted,
34 of 38
What does pitch depend on?
Frequency. The higher the frequency of the wave, the higher the pitch of the sound.
35 of 38
What does loudness depend on?
Amplitude. The greater the amplitude, the more energy the waves carry and so the louder the sound.
36 of 38
Where can different waveforms be shown?
An oscilloscope.
37 of 38
Why do instruments sound different?
The quality of a note depends on the waveform. Different instruments produce different waveforms.
38 of 38

Other cards in this set

Card 2

Front

How do transverse waves tavel?

Back

The oscillation (vibration) of the particles is perpendicular (at right angles) to the direction in which the wave travels.

Card 3

Front

How do longitudinal waves tavel?

Back

Preview of the front of card 3

Card 4

Front

What are electromagnetic waves and give examples of them?

Back

Preview of the front of card 4

Card 5

Front

What are mechanical waves and give an example of one?

Back

Preview of the front of card 5
View more cards

Comments

No comments have yet been made

Similar Physics resources:

Waves
Teacher recommended
See all Physics resources »See all Waves resources »