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1

Two different types of waves

- transverse
- longitudinal

2

Longitudinal Waves

The oscillations are perpendicular. To direction of energy transfer.

3

Transverse wave.

Oscillations parallel in the direction of energy transfer.

4

Amplitude =

Maximum displacement for equilibrium.

5

Wave length =

Crest to crest distance.

6

Frequency =

Waves per second

7

Period =

Time it takes for one wave. = 1 / Frequency.

8

Wavelengths in light are

Colours

9

Wave speed =

WS = Frequency x wavelength.

10

An example of longitudinal wave

Sound,

11

An example of transverse waves:

- light
- microwaves.

12

Refraction

A change of speed of the light ray in which changes its direction.

13

Going into a higher density medium

The light slows down and goes towards the normal.

14

Going out of a high density medium and into a lower one.

Light speeds up and moves away from the normals

15

Normals

Perpendicular to the surface the light is going through.

16

If an object is a certain colour (green)

Then it can only be see as green when the colour of the light shining on it has green in it.

17

Waves:

Transfer energy but without matter.

18

How the ear works:

In three sections:
- outer ear
- middle ear
And inner ear.

19

Outer ear:

- the pinna - the flesh of the ear which gets the sound waves into the ear cannel.

- ear canal - carries the sound to the ear drum and middle ear.

20

Middle ear:

- its filled with air, with the ossicles.
- the sound passes through here into the inner ear.
- also, contains the Eustachian tube connecting to your throat and nose, this is ventilating for the ear.

21

Inner ear.

Contains the cochlea and the semi circular cannel.

22

The cochlea

- in the inner ear.
- It has two chambers that are filled with liquid, with the ORGAN OF CORTI, changing the sound into electrical impulses for the brain.
- It has thousands of hairs and auditory nerves send signals to the brain.
- highest pitch at the top of the spiral picked by by hairs, lowest at the lowest.

23

The semi circular cannel

- in the inner ear.
- part of the balance system not for hearing.
- made of liquid and hair cells.
- send electrical impulses to the brain to see what direction we are in.

24

Human hearing span:

20hz - 20,000hz
- anything above is ultrasound.
- anything below is infrasound. (I think)(ultrasound is more important.)

25

Ultrasound:

Above 20,000hz we cant hear it.
Carries lots of energy.
Use it for imaging. Medical and distance. E.G sea bed

26

Inner core of earth.

- solid
- very very hot
- pressure is huge.

27

Outer core

-Liquid
-very hot
- pressure

28

Mantle

-Moltern
- hot not as hot.

29

Crust

-solid
- hard
- still hot.

30

Seismic waves P=

Longitudinal