Light Test

Question 1

What is the ‘period’ of waves?

Answer 1

The amount of time it takes to get from one crest to another

Question 2

What is the ‘frequency’ of waves?

Answer 2

the number of waves per second

Question 3

What is the ‘wavelength’ of waves?

Answer 3

the distance from one crest to another

Question 4

What is the name of the movement of waves at repeated intervals?

Answer 4

Periodic movement.

Question 5

If the period of a ripple of a lake is half a second or 0.5 s, what will be the frequency?

Answer 5

2 waves/second

Question 6

If a wavelength is long what does that mean for the frequency of the wave?

Answer 6

The frequency will be lower.

Question 7

As light is a wave, does it have a frequency?

Answer 7

YES

Question 8

Does ‘white light’ have a specific frequency?

Answer 8

No – that is because it is made up of 7 colours. Therefore it has different wave lengths from different colours.

Question 9

What did Newton discover?

Answer 9

White light consists of all colours of the visible spectrum. Red, orange, yellow, green, blue, Indigo, violet. When all colours shine at once they produce white light.

Question 10

Visible light

Answer 10

Each colour has it’s own wavelength and frequency.

Question 11

What is the violet spectrum?

Answer 11

This is violet light that has the highest frequency therefore it has the shortest wavelength.

Question 12

What is the relationship between the colours of the visible spectrum and the frequency of light waves?

Answer 12

Each colour corresponds to light waves with a different frequency. So, the colour we see depends on the frequency of the light waves entering our eyes.

Question 13

Explain Transmission

Answer 13

The light passes through an object

Question 14

Explain absorption

Answer 14

Light is transformed into heat inside an object

Question 15

Explain Reflection

Answer 15

Light bounces off an object

Question 16

What is opaque

Answer 16

No light passes through

Question 17

What is transparent

Answer 17

Light passes through

Question 18

What is translucent

Answer 18

Some light gets through

Question 19

Why does green light appear green?

Answer 19

It reflects mostly green and absorbs other frequencies

Question 20

Why white appear white?

Answer 20

it reflects all visible frequencies

Question 21

Why do objects appear blacker out of the sun?

Answer 21

Black objects absorb most of the heat/light that hits them and converts it to heat.

Question 22

Why does a blue object look blue in the sun?

Answer 22

because only blue light reflects off of it, the other ms are turned into heat

Question 23

What is refraction and how does it link to light?

Answer 23

It occurs when alight ray bends as it passes from one material into another.

Question 24

Tell me about refraction and reflection?

Answer 24

Both refraction and reflection involve light rays changing direction.

Question 25

Why does ‘light’ traveling from air into glass block change direction?

Answer 25

It slows down

Question 26

What happens with white light and a prism?

Answer 26

A prism can separate white light into the visible spectrum because different frequencies are refracted by different amounts.

Question 27

What are the differences between reflection and refraction?

Answer 27

1. Refraction involves light passing across a boundary from 1 material to another whereas reflection does not.
2. Refraction involves a change in the light’s speed where as reflection does not.

Question 28

What senses curve inwards?

Answer 28

The senses that curve inwards and are thinner in the middle are called concave.

Question 29

Why is a magnifying glass ‘convex?

Answer 29

A magnifying glass makes objects appear larger than they really are. This is because they are convex.

Question 30

What is the focal length of a lens?

Answer 30

The focal length of a lens is the difference from the focal point to the centre of the lens.

Question 31

What type of lens is the human eye?

Answer 31

The human lens in the eye cause light rays to converge so it is convex.