P6 Waves

Question 1

Define longitudinal waves

Answer 1

The direction of oscillation is PARALLEL to the direction of energy transfer

Question 2

Define transverse waves

Answer 2

The direction of oscillation is PERPENDICULAR to the direction of energy transfer

Question 3

2 examples of LONGITUDINAL waves

Answer 3

Sound
Seismic P waves

Question 4

4 examples of TRANSVERSE waves

Answer 4

Water waves
Seismic S waves
Light
EM waves

Question 5

Waves transfer _____ without transferring ______

Answer 5

ENERGY without transferring MATTER

Question 6

What is a wave length (M)

Answer 6

The length of one complete wave

Question 7

What is the time period (S)

Answer 7

The time taken for one wave to pass

Question 8

What is the frequency of waves (Hz)

Answer 8

The number of waves that pass every second

Question 9

We can use a ripple tank to find ….

Answer 9

Frequency

Question 10

How to measure speed of sound waves

Answer 10

-Attach a microphone to an oscilloscope
-Clap once next to microphone
-Measure how long it takes for echo to return the microphone from a wall that is a known distance away
-Use oscilloscope to measure time taken
-Then do total distance divided by time

Question 11

What is the human hearing range

Answer 11

20hz to 20Khz

Question 12

If frequency is greater than 20kHz it is known as

Answer 12

Ultrasound

Question 13

Ultrasound is above __kHz

Answer 13

20

Question 14

How do we hear sound waves

Answer 14

They cause your eardrum to vibrate, which sends a signal to your brain

Question 15

How can we use ultrasound to see a baby in a pregnant lady

Answer 15

The ultrasound waves are reflected back when they meet the baby

Question 16

Seismic P waves or Seismic S waves travel through liquid

Answer 16

Seismic P waves can

Question 17

Longitudinal waves can or can’t travel through liquid

Answer 17

Longitudinal waves CAN travel through liquid

Question 18

Transverse waves can or can’t travel through liquid

Answer 18

Transverse waves CANT travel through liquid

Question 19

Evidence for a molten core in the earth

Answer 19

After an earthquake, P-waves(longitudinal) can be recorded on the other side of the earth, however, S-waves (transverse)cannot so there must be a molten/liquid core

Question 20

If a light reflects off of a SMOOTH surface, this is

Answer 20

SPECULAR REFRACTION

Question 21

A rough surface will SCATTER light, this is called

Answer 21

DIFFUSE refraction

Question 22

Order of Electromagnetic wave spectrum
(R,M,I,V,UV,X,G)
Lower frequency ➡️ Higher frequency

Answer 22

Radio waves
Microwaves
Infrared
Visible light
Ultra Violet
X-rays
Gamma rays

Question 23

Example of radio wave uses

Answer 23

Phones, TV, Wi-Fi

Question 24

Example of microwave uses

Answer 24

Cooking (absorbed by water)

Question 25

Example of infrared uses

Answer 25

Cooking (absorbed by surface)

Question 26

Example of visible light uses

Answer 26

Vision

Question 27

Ultra violet uses

Answer 27

Tanning (can cause skin cancer)

Question 28

Uses of X-rays

Answer 28

Medical scans (can be dangerous)

Question 29

Uses of gamma rays

Answer 29

Medical treatments (Also dangerous)

Question 30

All EM waves are emitted and absorbed by ______ apart from gamma rays which are emitted by______

Answer 30

ELECTRONS, NUCLEI

Question 31

UV, GAMMA and X-RAYS are all examples of ___________ radiation

Answer 31

Ionising

Question 33

Infrared practical - Showing matte black is the best emitter of infrared

Answer 33

-Use a Leslie cube, and fill it with hot water -Point an infrared detector at each four sides of the Leslie cube, making sure it is an equal distance away from the cube each time -Matte black is best emitter , then shiny black, then white, then shiny metallic

Question 34

Infrared RPA - why is an infrared detector better than a thermometer

Answer 34

Higher resolution

Question 35

Infrared RPA - showing matte black is the best absorber of IR

Answer 35

-Place an infrared heater in between two metal plate, one shiny metallic plate and one matte black -On the other side of the plates use Vaseline to attach a drawing pin -Switch on the heater and start timing -Record time it takes for Vaseline to melt and drawing pins to fall off -Drawing pin falls of matte black plate first, absorb more IR quicker

Question 37

When waves enter a new material, their ______ changes, as does their _____ angle. This is known as ______

Answer 37

SPEED, ANGLE, REFRACTION

Question 38

If the wave slows down when entering an object, it moves toward the_______

Answer 38

Normal

Question 39

When a wave slows down in an object, the angle of _______ is smaller than the angle of ________

Answer 39

Refraction is smaller than Incidence

Question 40

Light disperses through a prism because

Answer 40

Different wavelengths are refracted different amounts . (Blue most, red least)

Question 41

Real images can be ______ virtual images cannot

Answer 41

PROJECTED

Question 42

Magnification =

Answer 42

Image height _________________ Actual height

Question 43

How do we describe an images (3 pairs of things)

Answer 43

Real/ virtual Enlarged/ diminished Upright/ inverted

Question 44

An object appears a certain colour because it _____ those wavelengths and _____ others

Answer 44

Reflects, Absorbs

Question 45

What is a blackbody

Answer 45

A theoretical object that perfectly absorbs and emits all wavelengths of radiation

Question 46

What can we apply the black body model to as an approximation

Answer 46

Stars and Planets

Question 47

If the rate of ABSORPTION is greater than the rate of EMISSION, its temperature ______

Answer 47

INCREASES, which in turn increases the rate of emission

Question 48

We perceive different colours when different _____ of light are _______ by the retina

Answer 48

Wavelengths, Absorbed