light and sound

Question 1

Which letter represents the amplitude of a wave?

Answer 1

A

Question 2

In a longitudinal wave, areas where the particles are pushed together are called _______.

Answer 2

compression

Question 3

A louder sound will have a higher _______.

Answer 3

amplitude

Question 4

A high-pitched sound will have a higher _______.

Answer 4

frequency

Question 5

Give an example of a longitudinal wave

Answer 5

sound wave

Question 6

Give an example of a transverse wave

Answer 6

light wave

Question 7

An object which gives off light is known as _______.

Answer 7

luminous

Question 8

How can we see non-luminous objects?

Answer 8

They reflect light

Question 9

When light hits an object and ‘stops’, it is known as _______.

Answer 9

absorption

Question 10

When light hits an object and bounces off, it is known as _______.

Answer 10

reflection

Question 11

A material that lets light through without scattering is known as _______.

Answer 11

transparent

Question 12

What is an opaque material?

Answer 12

A material that does not allow light to pass through

Question 13

An object that scatters light as it passes through is known as _______.

Answer 13

translucent

Question 14

Label the normal line, angle of incidence, and angle of reflection.

Answer 14

See diagram

Question 15

How does the angle of incidence compare to the angle of reflection?

Answer 15

They are equal

Question 16

If we are drawing a reflected ray, which step is missing? 1. Extend the incident line to the surface. 2 _______.

Answer 16

Draw the normal line

Question 17

What is refraction?

Answer 17

The bending of light as it passes from one medium to another

Question 18

When does refraction occur?

Answer 18

When light changes speed in a different medium

Question 19

If the speed of a wave decreases as it moves into a new substance, it will bend _______.

Answer 19

towards the normal

Question 20

If the speed of a wave increases as it moves into a new substance, it will bend _______.

Answer 20

away from the normal

Question 21

When the angle of incidence is greater than the critical angle, what will happen to the light?

Answer 21

Total internal reflection occurs

Question 22

If all the light is reflected with a material, what is this known as?

Answer 22

Total internal reflection

Question 23

Give two examples of where total internal reflection is found in real-life applications

Answer 23

• Optical fibers
• periscope

Question 24

What is the name of the coloured circle around the pupil?

Answer 24

Iris

Question 25

What is the purpose of the lens in the eye?

Answer 25

To focus light onto the retina

Question 26

What do you call the black part of the eye?

Answer 26

Pupil

Question 27

What is the retina?

Answer 27

The layer of tissue at the back of the eye that senses light

Question 28

What is the purpose of the optic nerve?

Answer 28

To transmit visual information to the brain

Question 29

Why do we end up with an inverted image formed on our retina when we look at an object?

Answer 29

The lens inverts the image

Question 30

What three colours of light can our eyes detect?

Answer 30

* Red * Green * Blue

Question 31

What are the colours of the spectrum that make up white light?

Answer 31

* Red * Orange * Yellow * Green * Blue * Indigo * Violet

Question 32

The colour of a light depends on what feature of a wave?

Answer 32

Wavelength

Question 33

When light enters a prism and splits into the colours of the spectrum, what do we call this effect?

Answer 33

Dispersion

Question 34

Why does a blue object appear blue when a white light is shone upon it?

Answer 34

It reflects blue light and absorbs other colours

Question 35

Why do black objects appear black?

Answer 35

They absorb all wavelengths of light

Question 36

When red and green light are combined, what colour is formed?

Answer 36

Yellow

Question 37

When red and blue light are combined, what colour is formed?

Answer 37

Magenta

Question 38

When blue and green light are combined, what colour is formed?

Answer 38

Cyan

Question 39

Sketch a low-pitched sound becoming a high-pitched sound (the volume remains constant).

Answer 39

See diagram

Question 40

Sketch a quiet sound becoming a loud sound (the pitch remains unchanged).

Answer 40

See diagram

Question 41

If a sound is becoming lower pitched, what is decreasing?

Answer 41

Frequency

Question 42

If a sound is becoming lower in volume, what is decreasing?

Answer 42

Amplitude

Question 43

What formula can we use to calculate the speed of sound?

Answer 43

Speed = Distance / Time

Question 44

Do sound waves travel fastest in solid, liquid, or gas?

Answer 44

Solid

Question 45

Do light waves travel fastest through a solid, liquid, or gas?

Answer 45

Gas

Question 46

When calculating the speed of sound using an echo, what must you remember?

Answer 46

To divide the total distance by two

Question 47

List 3 key signs of a chemical reaction

Answer 47

* Change in colour * Production of gas *Solid is created without cooling

Question 48

What happens in a chemical reaction?

Answer 48

Atoms rearrange to form new substances

Question 49

What does not happen in a physical change?

Answer 49

The chemical composition does not change

Question 50

When balancing a chemical reaction, what must we not change?

Answer 50

The subscripts in the formulas

Question 51

What do we mean by a balanced chemical reaction?

Answer 51

The number of atoms of each element is the same on both sides

Question 52

What is wrong with this balanced equation? 2Ca + O2 = 2CaO

Answer 52

arrow instead of equal sign.the two in O2 should be subscript

Question 53

How do you identify an exothermic reaction?

Answer 53

It releases heat

Question 54

How do you identify an endothermic reaction?

Answer 54

It absorbs heat

Question 55

What is oxidation?

Answer 55

When an element combines with oxygen to form a compound

Question 56

What is combustion?

Answer 56

A chemical reaction that involves burning

Question 57

Rusting would be an example of what type of chemical reaction?

Answer 57

Oxidation