Topic 1 - Visible light and the solar system

Question 1

What is the geocentric model?

Answer 1

Everything orbited the earth.

Question 2

What is the heliocentric model?

Answer 2

All planets orbit the sun, which is at the centre of the universe.

Question 3

who thought of the heliocentric model?

Answer 3

Copernicus

Question 4

What evidence helped support the heliocentric model?

Answer 4

Galileo discovered moons orbiting jupiter which showed that not everything was orbiting the earth proving the geocentric model wrong

Question 5

what does the current model state?

Answer 5

all the planets in our solar system orbit the sun but these orbits are elliptical rather than circular

Question 6

What did early astronomers use to study the stars

Answer 6

naked eye but this was only useful for mapping things positions

Question 7

What are the advantages of telescopes?

Answer 7

magnify images so they can be seen in more detail.
see objects at larger distances
help learn what the universe is made of.
Can be sent into space to avoid light being absorbed by the atmosphere
Can use cameras

Question 8

What advantages are there for using digital cameras with telescopes

Answer 8

Can ‘zoom in’ to see things in more detail
makes it easier to monitor an object by taking pictures at different times.
Can see faint objects by allowing a long exposure time.

Question 9

What is wavelength

Answer 9

the distance from one peak to the next

Question 10

What is frequency

Answer 10

how many complete waves there are per second. Measured in hertz

Question 11

What is amplitude

Answer 11

The height of the wave from the midline to the peak

Question 12

What do waves transfer

Answer 12

energy and information without transferring matter

Question 13

What is a transverse wave

Answer 13

the vibrations are perpendicular to the direction of travel

Question 14

give examples of transverse waves

Answer 14

EM waves

S-Waves

Question 15

What is a longitudinal wave

Answer 15

the vibrations are parallel to the direction of travel

Question 16

give examples of longitudinal waves

Answer 16

Sound

P-Waves

Question 17

What is an oscilloscope

Answer 17

shows things as transverse waves even sound

Question 18

what is the relationship between the angle of incidence and the angle of reflection when a wave is reflected

Answer 18

i = r

Question 19

Why is light reflected

Answer 19

when theres a change in destiny some of the wave is reflected

Question 20

What happens when a wave is refracted?

Answer 20

the material its travelling in changes density so the speed changes and sometime the direction of the wave

Question 21

What happens when a wave goes into a denser material

Answer 21

it slows down and the direction moves towards the normal

Question 22

What is a real image

Answer 22

When the light from an object comes together to form an image on a ‘screen’

Question 23

What is a virtual image

Answer 23

When rays of light are diverging so the light from the object appears to be coming from a completely different place

Question 24

Give an example of a virtual image

Answer 24

Magnifying glass

Reflection

Question 25

What is a converging lens

Answer 25

convex (blues outwards)
Causes parallel rays of light to move together (converge) and focus
Focal point is where rays hitting the lens parallel to the axis meet
Image is flipped

Question 26

Describe an experiment to find the focal length of a lens

Answer 26

Clamp lens to one end of a track, clamp piece of white card further down the track.
Set up the equipment near a window with the lens directed at a distant object.
Move card along the track until the image is focused and clamp it so it doesn’t move.
Measure the distance between the centre of the lens and the card and thats the focal length

Question 27

Describe a refracting telescope

Answer 27

Objective lens focuses the rays of light to form a real image at the focal point. the eyepiece lens then magnifies the image so you can see it

Question 28

describe a reflecting telescope

Answer 28

A large concave mirror (primary mirror) collects the light and reflects the light onto a smaller concave mirror in front of the focal point. The smaller mirror (secondary mirror) reflects light through a hole in the centre of the primary mirror and an eyepiece lens magnifies the image so you can see it.