Waves

Question 1

What are transverse waves?

Answer 1

Oscillations perpendicular (right angle) to direction of energy transfer

Question 2

Example of transverse waves?

Answer 2

Ripples on surface of water

Question 3

How to know that transverse waves are at right angles/perpendicular?

Answer 3

The T, can draw a right angle in it

Question 4

What are longitudinal waves?

Answer 4

Oscillations are parallel to energy transfer direction

Question 5

Examples of longitudinal waves?

Answer 5

Areas of compression/rarefraction like 🔊

Question 6

What is rarefraction?

Answer 6

Region in longitudinal wave where particles are further apart

Question 7

How to remember that longitudinal are parallel?

Answer 7

The bottom line of L shows that they are going parallel in a straight line

Question 8

What do waves transfer?

Answer 8

Energy and info without transferring matter

Question 9

Define amplitude?

Answer 9

Maximum displacement of a point on a wave from it’s undisturbed position

Question 10

Define wavelength?

Answer 10

Distance from a point on one wave to the same point on the next wave

Question 11

What is frequency?

Answer 11

Number of waves passing a point each second

Question 12

Define period in terms of waves?

Answer 12

Time taken for a wave to pass a fixed point 👉 👈

Question 13

What is wave speed/velocity?

Answer 13

Speed at which energy is transferred through a medium

Question 14

What can be used to measure the speed of ripples on 💧surface?

Answer 14

×Stroboscope
×Ripple tank

Question 15

What is wave speed?

Answer 15

Speed at which energy is transferred through a medium

Question 16

What type of wave are electromagnetic waves?

Answer 16

Transverse

Question 17

What do electromagnetic waves do?

Answer 17

●Transfer energy from thr source to an absorber
●Form a continous spectrum
●Travel at the same velocity through a vacuum or air

Question 18

Lowest frequency wave?

Answer 18

Radio waves

Question 19

Highest frequency wave?

Answer 19

Gamma rays

Question 20

Mmeumic to remember the order of frequency of magnetic waves?

Answer 20

Radio waves (Ronald)
Micro waves (Mcdonald)
Infrared (Invented)
Visible light (Very)
Ultraviolet (Unsusual)
X-rays (eXcellent)
Gamma rays (Gherkins)

Question 21

What are the 4 things that happen to electromagnetic waves?

Answer 21

•Reflected
•Refracted
•Absorbed
•Transmitted

Question 22

Wavelengths can be absorbed, reflected, refracted or transmitted but what does this depend on?

Answer 22

Type of substance and surface

Question 23

What is refraction?

Answer 23

When a wave changes direction as it travels from ond medium to another

Question 24

When does refraction occur?

Answer 24

When the wave changes speed as it moves between media

Question 25

Do waves have different velocities (speed) in different media?

Answer 25

Yes

Question 26

What happens when light passes from water to air?

Answer 26

Light rays bend away from the normal

Question 27

What happens when the edge of the first light wave hits the water (wave front diagram)?

Answer 27

Slows down whilst the rest of the wave continues at the sane speed, causes light to bend towards the nornal

Question 28

How are electromagnetic waves generated/absorbed?

Answer 28

Due to changes in atoms

Question 29

How do gamma rays form?

Answer 29

From the changes in the nucleus of an atom

Question 30

How are radio waves made?

Answer 30

Produced by oscillations in electrical circuits, when absorbed create an alternating current with same frequency as radio waves

Question 31

Examples of radio waves?

Answer 31

-Television -Radio -Bluetooth

Question 32

How are radio waves transmitted?

Answer 32

Don't need direct line of sight between transmitter and reciever

Question 33

Examples of microwaves?

Answer 33

-Satellite communications -Cooking food

Question 34

How microwaves transmitted?

Answer 34

Small wavelength so able to be directed in narrow beams

Question 35

Examples of infrared?

Answer 35

-Electrical heaters 🔥 -Cooking food 🍳

Question 36

How is infrared transmitted?

Answer 36

Thermal radiation heats object

Question 37

Examples of visible light?

Answer 37

-Fibre optic communications

Question 38

How is visible light transmitted?

Answer 38

Reflected down fibre optic cable

Question 39

Examples of ultraviolet?

Answer 39

-Sun beds 🛌 -Energy efficient lamps 💡

Question 41

How are ultraviolet waves used?

Answer 41

Used for low energy light bulbs to produce white light, requires less energy than filament

Question 42

Examples of x-rays?

Answer 42

-Medical imaging + treatments

Question 43

How do x-rays work?

Answer 43

Absorbed more by hard tissue like bone, less by soft tissue, allows images of inside body to be created

Question 44

Uses of gamma rays?

Answer 44

-Sterilising -Medical imaging -Cancer treatment

Question 45

How gamma rays work?

Answer 45

Destroy living cells so can Sterilise medical equipment, destroy cancerous cells, organ scans

Question 46

How is electromagnetic measured ?

Answer 46

By sieverets

Question 47

How many sieverets is 1000 millisieverts (mSv)?

Answer 47

1 sievert

Question 49

Dangers of ultraviolet ?

Answer 49

Cause skin to age prematurely, increase risk of skin cancer

Question 50

What can microwaves do to body cells?

Answer 50

Cause internal heating of body cells

Question 51

What does the effect of the electromagnetic wave depend on?

Answer 51

Type of radiation + size

Question 52

What are sieverts a measure of?

Answer 52

Risk of harm

Question 53

What 3 waves have a hazardous effect on body?

Answer 53

-Ultraviolet -X-rays -Gamma rays

Question 54

Why waves are ionising?

Answer 54

X-rays + Gamma rays