Chapter 3- Heat, Light and Sound

Question 1

What does heating a substance do?

Answer 1

Adds energy to the particle

Question 2

What happens when an object is heated?

Answer 2

The particles start to vibrate more and more and also expand as they move apart

Question 3

How do substances change state?

Answer 3

When the particles vibrate so much that they break free from one another and change state

Question 4

What is conduction?

Answer 4

How heat travels through solids

Question 5

How does conduction work?

Answer 5

Hotter substances have particles that vibrate faster and as heat flows from areas of higher temperature to lower, the particles cause other particles to vibrate and the heat spreads.

Question 6

What are conductors and insulators?

Answer 6

Conductors are substances that transfer heat easily. Insulators are substances that are poor conductors or even block heat completely

Question 7

What are some examples of good conductors?

Answer 7

Metals e.g Gold, Nickel, Iron

Question 8

What are some examples of good insulators?

Answer 8

Plastic, air and cloth

Question 9

How does a thermos flask work?

Answer 9

They create a vacuum between the substance inside and the substance outside, meaning that heat cannot get inside

Question 10

What is convection?

Answer 10

How heat travels in liquids and gases

Question 11

How does convection work?

Answer 11

As air is heated, and because hot air is less dens than cool air, causing it to rise, the airflow of the rising and falling air creates an airflow called a convection current

Question 12

What are some examples of convection?

Answer 12

Things like sea breezes and hot water systems

Question 13

What is radiation?

Answer 13

Because space is a vacuum, heat from the sun cannot be transferred through conduction or convection because there are no particles so it transfers through radiation.

Question 14

How does radiation work?

Answer 14

The heat transmits itself as an invisible wave that travels at the speed of light and is known as an Infrared (IR) wave

Question 15

What happens when radiated energy hits a surface?

Answer 15

It is either absorbed, reflected or transmitted depending on the substance and colour

Question 16

What type of colours absorb, reflect or transmit?

Answer 16

Dark colours absorb heat, light colours reflect and clear materials transmit hea

Question 17

How is sound produced?

Answer 17

When vibrations create compressions and rarefractions

Question 18

What substances can sound transmit through and what can it transmit through the best?

Answer 18

It transmits through solids the best, then liquids, then gases and not at all through a vacuum because it relies on particles to move

Question 19

How does a transverse wave move? And what are some examples?

Answer 19

Up and down or side to side. Examples are light waves and secondary waves

Question 20

How does a longitudinal wave move and what are some examples?

Answer 20

Back and forth in the same direction the wave is travelling and examples are sound waves and Primary Waves

Question 21

What speed does sound travel at through normal air temperature?

Answer 21

Around 340m/s

Question 22

What type of surfaces reflect sound and what is it heard as?

Answer 22

Hard surfaces such as concrete reflect sound waves and it is heard as an echo

Question 23

What types of materials absorb sound?

Answer 23

Soft materials such as carpet

Question 24

How does sonar work?

Answer 24

The sound reflect off a hard surface and is heard as an echo and the time difference can be used to calculate the depth of something underwater

Question 25

What produces a higher pitch or frequency?

Answer 25

The faster the particles vibrate

Question 26

What is frequency?

Answer 26

The number of vibrations a sound makes per second. It is measured in hertz

Question 27

What is the wavelength?

Answer 27

The distance between two crests or trenches

Question 28

What is amplitude?

Answer 28

How loud a sound is and the larger the peak of a wave, the higher the amplitude

Question 29

What is the relationship between frequency and wavelength?

Answer 29

Sound that have a higher frequency produce sound waves with a shorter wavelength

Question 30

What is the equation for a wave?

Answer 30

Velocity (which is always the same) which equals Frequency times wavelength

Question 31

What are the parts and their functions of the outer ear?

Answer 31

The Pinna which funnels sound into the ear canal | The Eardrum which vibrates the sound and separates the outer and middle ear

Question 32

What are the parts and their functions of the Middle ear?

Answer 32

The Ossicles- 3 bones (hammer, anvil and stirrup) that magnify the vibrations Oval Window- Transmits vibrations to the cochlea and separates Middle and Inner Ears

Question 33

What are the parts and their functions of the Inner Ear?

Answer 33

Eustachian Tube- Connects to the nose and throat and controls the air pressure which stops the eardrum from bursting Semicircular Canals- Control our sense of balance Cochlea- Vibrations are detected by tiny hairs in the cochlea which convert the movement into electrical impulses Auditory Nerve- Transmits the electrical impulses to the brain

Question 34

What types of things are used to fix hearing?

Answer 34

Hearing Aids magnify the sound and enable people to hear better. Cochlea implants replace the cochlea and can fix deafness

Question 35

What can happen when light hits a surface?

Answer 35

It is either transmitted through it, reflected off it or absorbed into it

Question 36

What happens when light hits a transparent object?

Answer 36

Almost all light is transmitted through it and a clear image can be seen through it. E.g clear glass or shallow water

Question 37

What happens when light hits a translucent material?

Answer 37

Some light maybe be reflected and light that passes through it is scattered, an image can be seen through it but it is fuzzy. E.g. Tissue paper, frosted glass

Question 38

What happens when light hits an opaque material?

Answer 38

Light is either reflected from or absorbed into the surface. No light is transmitted and no image can be seen through it. E.g brick, wood etc

Question 39

What is the law of reflection?

Answer 39

Angle of incidence equals angle of reflection

Question 40

What is the 'normal'?

Answer 40

An imaginary line that goes through the middle of the two Rays

Question 41

What happens when a plane mirror produces an image of an object?

Answer 41

It creates a virtual image

Question 42

When does light refract?

Answer 42

When it travels through substances of different optical density

Question 43

Why does light refract?

Answer 43

Light travels at different speeds through different substances and the difference in speed results in different amounts of bending

Question 44

What happens when light enters a denser substance?

Answer 44

It bends towards the normal and slows down

Question 45

What happens when light enters a less dense substance?

Answer 45

It bends away from the normal and speeds up

Question 46

A lens that bulges outwards is called a?

Answer 46

Convex lens

Question 47

What do convex lenses do to light rays?

Answer 47

They cause the light rays to come together or converge

Question 48

Do convex lenses produce virtual or real images?

Answer 48

Real images

Question 49

What type of lens do we have in our eyes?

Answer 49

A convex lens

Question 50

A lens that curves inwards is called a?

Answer 50

Concave lens

Question 51

What do concave lenses cause light to do?

Answer 51

Diverge or spread out

Question 52

What times of images do concave lenses produce?

Answer 52

Virtual images

Question 53

What are the parts of the eye?

Answer 53

Cornea, Iris, Pupil, Sclera, Aqueous Humour, Lens, Ciliary Body, Vitreous Humour, Retina, Optic Nerve

Question 54

How does light travel through the eye?

Answer 54

It is refracted by the cornea and goes through the pupil to the lens where it is focused as a clear upside-down image onto the retina which turns in into electrical impulses and sends it to the brain via the optic nerve

Question 55

What is the function of the cornea, sclera, Iris and pupil?

Answer 55

The cornea refracts the light into the eye The Iris enlarges and shrinks the pupil to control light flow The pupil is a hole that determines amount of light allowed in The sclera is the white of the eye

Question 56

What is the function of the aqueous humour, lens and ciliary body?

Answer 56

The aqueous humour is a clear liquid that separates the lens and cornea The lens focuses the light onto the retina The ciliary body changes the shape of the lens

Question 57

What is the function of the vitreous humour, retina and optic nerve?

Answer 57

The vitreous humour is the clear fluid between the lens and retina. The retina converts light into electrical impulses The optic nerve carries electrical impulses to the brain