Waves(p)(p1/2)

Question 1

Are waves sometimes, always or never reflected

Answer 1

Sometimes

Question 2

What can happen to waves(3)

Answer 2

Reflected, absorbed and transmitted

Question 3

What is the angle incident to the angle reflection

Answer 3

Always equal

Question 4

What is speculation reflection

Answer 4

Occurs on flat surface, producing a clear image.

Question 5

What is diffuse reflection?

Answer 5

Occurred on material with bumpy surface, meaning reflection is not so clear

Question 6

What is a wave?

Answer 6

Transfers energy from one place to another

Question 7

What is the wavelength?

Answer 7

The distance of the entire oscillation

Question 8

What is a longitudinal wave

Answer 8

Oscillations that are parallel to direction of energy transfer(exp: sound waves, seismic waves)

Question 9

What is a transverse wave?

Answer 9

Oscillations that are perpendicular to direction of energy transfer(exp: electromagnetic waves[light, radio, string])

Question 10

What occurs at refraction of light waves?

Answer 10

They change direction as they pass from one medium to another

Question 11

Why do waves travel at different speeds In different material?

Answer 11

They have different different densities

Question 12

What does it mean when there’s higher density? (To waves)

Answer 12

The waves are slower

Question 13

What happens to waves that travel at an angle to more dense areas?

Answer 13

Will align towards the normal. Called refracted ray

Question 14

What happens when waves travel at an angle to less dense area?

Answer 14

They bend away from normal (emergency ray)

Question 15

What happens to the waves when they pass through different medians?

Answer 15

The speed of the waves changes

Question 16

What is the formula which includes wave speed, frequency and wavelength

Answer 16

Wave speed = frequency x wavelength

Frequency stays the same

Wavelength decreases

Speed increases

Question 17

What are electromagnetic waves?

Answer 17

They are transverse and travel at different speeds.

Question 18

What are the different electromagnetic waves?

Answer 18

Radio waves
Microwaves
Infra red waves
Visible light
Ultra violet
X-rays
Gamma rays

Question 19

What are gamma rays made from?

Answer 19

Radioactive decay

Question 20

What are ultraviolet’s made from?

Answer 20

From electrons dropping down energy levels

Question 21

Where do InfrA red waves come from?

Answer 21

Bonds that hold molecules together vibrate

Question 22

How fast do electromagnet travel?

Answer 22

3x10(8) m/s

Question 23

What do radio waves have?

Answer 23

Long wavelengths and low frequencies

Question 24

What are electromagnetic waves made from?

Answer 24

Oscillating electric and magnetic fields

Question 25

What radio waves have long wavelengths and lower frequencies than visible light?

Answer 25

Radio waves
-microwaves
-infrared waves

Question 26

How do you generate radiowaves?

Answer 26

Requires transmitter, oscilloscope, and receiver

-The transmitter is connected to the oscilloscope to see frequency of alternating current. Which can be then used to determine frequency of wave

-receiver absorbs energy from transmitter, generating an alternating current that is connected to oscilloscope, which produces same frequency as transmitter wavelength

Question 27

How do you use radio waves for long communication?

Answer 27

-long waves: can travel huge distances by bending around the curved surface of the earth
-short waves: travel long distances by being reflected upon the ionosphere

Question 28

How do you use radio waves for short communication?

Answer 28

-short waves: blue tooth between phones

-very shot waves directly receive waves from transmitter

Question 29

What 2 types of methods can be used for microwaves?

Answer 29

1. Absorbing water: this is done via microwaves heating the food by water molecules in the food absorbing microwaves that then transfer energy to neighbour molecules via conduction and convection.
2. Not absorbed: passes through atmosphere and received by satellite, that is then transmitted to satélite dish

Question 30

What are infrared waves?

Answer 30

They are emitted from all objects that have thermal energy. Where the more hotter and object is, the more infrared radiation emitted.

Question 31

What can infrared radiation be used for?

Answer 31

-infrared cameras: make us spot living organisms
-cooking in ovens, emit lots of radiation that heat food by transferring heat energy
(Harmful in large quantities)

Question 32

What are UV lights used for?

Answer 32

-sun beds to get a tan
-sterilising water
-security to write secret messages

Question 33

What is fluorescence?

Answer 33

Ultraviolet light absorbed and remitted as visible light

(Used in fluorescent light, to generate ultraviolet and absorb phosphorus, environmentally friendly )

Question 34

What is visible light used for?

Answer 34

Humans to see

-communication via optical fibres. That are fin plastic or glass fibres that transmit pulses of light long distances as light is reflected (specular) every time it hits the surface
(Transmits data very quickly)

Question 35

What are X-rays used for?

Answer 35

-view internal structure of objects, fire X-rays through body, That is received by detector plate .

[This is possible due to bones absorbing X-rays for being dense and that they pass through parts in body mostly air (lungs and intestine) (partially through fleshy parts, heart)]

-can detect broken bones

Question 36

Who are X-rays dangerous for?

Answer 36

-for staff , so where lead aprons
-and give small amount of radiation to patient

Question 37

What are gamma rays used for?

Answer 37

-medical imaging
-treat cancer
-sterilising microorganisms whiteout any other damage made to rest of object(used in medical equipment and food)

-although it is ionising radiation that can damage our cells. This could cause Vance but can be use to treat disease and diagnose it