Waves

Question 1

How do waves work?

Answer 1

transfer information & energy without transferring matter

Question 2

What type of waves are transverse?

Answer 2

em waves

Question 3

Which direction do transverse waves vibrate?

Answer 3

perpendicular to direction of wave travel

Question 4

What type of waves are longitudinal?

Answer 4

sound & ultrasound waves

Question 5

What direction to longitudinal waves vibrate?

Answer 5

parallel to direction of travel

Question 6

Compressions

Answer 6

areas where particles are bunched up

Question 7

Rarefactions

Answer 7

areas where particles are spread out

Question 8

Peak

Answer 8

the highest point of a wave.

Question 9

trough

Answer 9

the lowest point of a wave.

Question 10

wavelength

Answer 10

the length of one wave i.e. the distance from peak to peak (or trough to trough)

Question 11

frequency

Answer 11

the number of waves passing a point each second, measured in hertz (Hz). 1 Hz is equivalent to 1 wave per second.

Question 12

What is the relationship between frequency & pitch?

Answer 12

larger the frequency, the higher the pitch

Question 13

ampitude

Answer 13

the height of a wave, measured from the resting point to its peak.

Question 14

What is the relationship between amplitude & volume?

Answer 14

the larger the amplitude, the higher the volume

Question 15

period

Answer 15

the time taken in seconds for one complete wave to pass a point

Question 16

What type of waves are sound waves?

Answer 16

longitudinal

Question 17

What does the speed of sound depend on?

Answer 17

medium through which it is travelling,
sound waves require particles to carry the vibration so they can’t travel through a vacuum

Question 18

What are electromagnetic (EM) waves?

Answer 18

Transverse waves, meaning the vibrations move up and down (at right angles) to the direction of wave travel.

Question 19

Do EM waves require particles to carry vibrations?

Answer 19

No, unlike sound waves, EM waves do not require particles to carry the vibrations.

Question 20

Can EM waves travel through a vacuum?

Answer 20

Yes, because they do not require particles to carry the vibrations.

Question 21

How many types of EM waves are there?

Answer 21

Seven different types.

Question 22

What is the electromagnetic spectrum?

Answer 22

An organization of the different types of EM waves along a spectrum.

Question 23

Do all EM waves travel at the same speed through a vacuum?

Answer 23

Yes, all EM waves travel at the same speed through a vacuum.

Question 24

What differs between different types of EM waves?

Answer 24

Their wavelengths and frequencies.

Question 25

What are the waves on the EM spectrum called?

Answer 25

R - radio waves M - microwaves I - infrared radiation V - visible light U - ultraviolet X - x-ray G - gamma radiation

Question 26

Radio Waves uses

Answer 26

Have the longest wavelength, making them good at transmitting information over long distances. Used for TV and radio broadcasting.

Question 27

Microwaves uses

Answer 27

Used for satellite TV and mobile phone communications. Also used in microwave ovens to heat up food.

Question 28

Infrared radiation uses

Answer 28

Essentially heat. Detected by night-vision equipment and used by heating devices, such as electric heaters and grills.

Question 29

Visible light uses

Answer 29

Used to see our surroundings. Also used for communication with optical fibers and in photography.

Question 30

Ultraviolet uses

Answer 30

Fluorescence occurs when a fluorescent material absorbs UV light and emits visible light. Used in fluorescent lamps and detecting forged banknotes. Emitted naturally by the Sun and artificially by sunbeds.

Question 31

X-ray uses

Answer 31

Used to see internal structures of objects, useful for detecting broken bones and fractures.

Question 32

Gamma radiation uses

Answer 32

Has the highest frequency. Effective at killing microbes, used to sterilize food and medical equipment.

Question 33

What are the dangers of microwaves?

Answer 33

Internal heating of our body tissue is dangerous so microwave ovens have a coating to shield the waves from the user.

Question 34

What are the dangers of infrared?

Answer 34

skin burns and in more extreme cases, skin cancer. Insulating materials can be used to protect against the effects of infrared radiation.

Question 35

What are the dangers of ultraviolet?

Answer 35

damage to surface cells and blindness. When they enter cells they can mutate the DNA which leads to cancer. Suncream is used as a protective measure to reduce exposure to UV.

Question 36

What are the dangers of gamma?

Answer 36

penetrate cells and mutate the DNA, leading to tissue damage or cancer. People who have to work with gamma radiation, such as doctors, will limit the amount of time they are exposed. The sources of gamma rays are also kept in a box lined with lead