Waves

Question 1

What are electromagnetic waves

Answer 1

They are transverse waves that transfer energy from the source of the waves to an absorber

Question 2

What might waves be

Answer 2

Transverse or longitudinal

Question 3

What are the ripples on water surface area examples of

Answer 3

A transverse wave

Question 4

What do longitudinal waves show areas on

Answer 4

Compression and refraction

Question 5

Give an example of longitudinal wave

Answer 5

Sound waves traveling through the air

Question 6

What is the frequency of a wave

Answer 6

The number of waves passing a point each second

Question 7

What is the wavelength of a wave

Answer 7

The distance from a point on one wave to the equivalence point on the adjacent waves

Question 8

What is the amplitude of a wave

Answer 8

The maximum displacement of a point on a wave away from its undisturbed position

Question 9

What is the wave speed

Answer 9

The speed at which the energy is transferred (or the wave moves) through the medium

Question 10

it moves up and down what do scientists called this movement

Answer 10

Oscillations

Question 11

How do sound waves travel

Answer 11

As particles in the air moving from side to side

Question 12

For longitudinal waves particles that are very close together are called what

Answer 12

Compressions

Question 13

For longitudinal waves particles that are spaced out are called what

Answer 13

Rarefractions

Question 14

What is the difference between longitudinal waves and transverse waves

Answer 14

Longitudinal waves: The oscillations are parallel to the direction of energy transfer and they require a medium to travel in (eg. Air, liquid, solid)

Transverse waves: The oscillations are perpendicular (At right angles) to the direction of energy transfer and (moves up and down but the direction of energy transfer is sideways) and not all transverse waves require a medium.

Question 15

It’s the wave that travels not the water or air how can you test for this

Answer 15

Using a slinky

Question 16

What does the slinky do

Answer 16

Shows transverse waves this represents ripples on the surface area of water (The red dot shows a single point eg. Water molecule)

Shows longitudinal waves and this represents sound waves traveling through and the red dot represents an air particle 

Question 17

Required practical: How to use a ripple tank to measure…

Question 18

What do electromagnetic waves form

Answer 18

A continuous spectrum

Question 19

What do all types of electromagnetic waves travel at

Answer 19

The same velocity through a vacuum (space) or air

Question 20

How are the waves that form of electric magnetic spectrum grouped

Answer 20

In terms of the wave length and frequency going from long to short (or from low to high frequency)

Question 21

Name all the types of electric magnetic waves going from long to short wavelength (Low frequency to high frequency)

Answer 21

Radio waves
microwaves
infrared
visible light
ultraviolet
x-rays
Gamma rays

(Raw meat is very unsanitary except giraffe)

Question 22

Human eyes only detect visible light meaning

Answer 22

A limited range of electromagnetic waves are detected by us

Question 23

From radio waves to gamma rays what happens to the frequency

Answer 23

The frequency increases

Question 24

What happens to the wavelength from radio waves to gamma waves

Answer 24

The wavelength decreases

Question 25

How can electromagnetic waves travel

Answer 25

Through a vacuum example space

Question 26

All electric magnetic waves travel at the same speed in a vacuum what is the speed

Answer 26

300000000m/s (3x10^8m/s)

Question 27

What do different materials/substances do to electromagnetic waves

Answer 27

Absorb, transmit, refract or reflect electromagnetic waves in ways that vary with wavelengths

Question 28

What is refraction due to

Answer 28

difference in velocity of the wavelength in different substances

Question 29

What happens in refraction

Answer 29

Waves can change direction when they change speed moving from one medium to another

Question 30

Required practical: How to investigate Emission with a Leslie cube

Answer 30

You can use a Leslie’s cube to see how much infrared is emitted from different surfaces (Types of surfaces: shiny metallic, white surface, shiny black, matte black) Put the cube on a heatproof mat Boil water in a kettle and fill the cube Fill the Leslie’s cube with hot water Point an infrared detector at each of the four surfaces and record the amount of infrared emitted And keep the same distance between the cube and the detector Most to least emitted infrared radiation: Matt black, shiny black, white, shiny metallic. If we do not have an infrared detector we can use a thermometer with a bulb painted black but the resolution of the thermometer is less than the infrared detector And record the amount of RI radiation Repeat for each of the cubes faces make sure the distance is the same (Be careful moving the cube full of boiling water you might burn your hands)

Question 31

Required practical: How to investigate absorption with the metal wax trick

Answer 31

Get an infrared heater and on each side have two metal plates one plate painted with shiny metallic paint and another with black matte paint Use Vaseline to attach a drawing pin Switch on the heater and start the timer The temperature of the metal plates increase as they absorb the infrared Record the time it takes for the Vaseline to melt and the drawing pins to fall off It falls off the mat black plate first because they absorb more infrared than shiny metallic surfaces The infrared tends to be reflected from the shiny metallic surface

Question 32

What happens when the electromagnetic waves are generated or absorbed

Answer 32

Changes take place in atoms are in the nuclei of atoms

Question 33

What happens when we heat atoms

Answer 33

We caused the electrons to move from one energy level to a higher one

Question 34

What does a change to an atom cause

Answer 34

It generates an electromagnetic wave

Question 35

What happens when electromagnetic waves are absorbed

Answer 35

It causes changes to atoms

Question 36

What do ultraviolet waves increase a risk of

Answer 36

Skin cancer and causes the skin to age

Question 37

What are x-rays and gamma rays considered as

Answer 37

Ionizing radiation

Question 38

What do x-rays and gamma rays cause

Answer 38

Mutations of genes and increase the risk of cancer

Question 39

How can radio waves be produced

Answer 39

By oscillations in electrical circuits

Question 40

1000 mSv = ? Sv

Answer 40

1 Sv

Question 41

What happens when radio waves are absorbed

Answer 41

They may create an alternating current with the same frequency as the ratio wave itself so the radio waves can themselves include oscillations in an electrical circuit

Question 42

Ultraviolet waves, x-rays and gamma rays have hazardous effect on the human body tissue what do the effects depend on

Answer 42

The type of radiation on the size of the dose

Question 43

What can radio waves be used for

Answer 43

Television and radio

Question 44

What can microwaves be used for

Answer 44

Satellite communications cooking food

Question 45

What can infrared radiation be used for

Answer 45

Electrical heaters cooking food infrared cameras

Question 46

What can visible light be used for

Answer 46

Fiber optic communications

Question 47

What can ultraviolet radiation be used for

Answer 47

Energy efficient lamps sun tanning

Question 48

What can x-rays and gamma rays be used for

Answer 48

Medical imaging and treatments