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Question 1

When was the universe formed?

Answer 1

5 billion years ago

Question 2

What is the Earth’s diameter?

Answer 2

13’000 km

Question 3

What is the sun’s diameter?

Answer 3

1’400’000 km

Question 4

What is the distance to the nearest star?

Answer 4

4.2 light years

Question 5

What is the distance to the nearest galaxy?

Answer 5

2’300’000 km

Question 6

Where does our evidence of distant stars and galaxies come from?

Answer 6

Radiation astronomers collect

Question 7

How fast does light travel?

Answer 7

300’000 km/s

Question 8

What is a light year?

Answer 8

The distance light travels in a year

Question 9

How can you measure the distance of star using the parallax effect?

Answer 9

Look at how far a nearby star moves against fixed stars in a specific time such as 6 months

Question 10

How can you measure the distance of a star using its relative brightness?

Answer 10

Two stars have the same real brightness.
They can have different relative brightnesses.
If you know the distance of one of the stars.
The difference in their relative brightness can be used to calculate the distance to the other one.

Question 11

Why are there uncertainties in measuring the distance to stars?

Answer 11

1. It is based on the assumption that similar types of stars have the same relative brightness
2. It is based on estimating the distance to one of the stars
3. Dust, rain, clouds and light pollution can make it difficult to measure stars at night

Question 12

Where does the sun get its energy from?

Answer 12

Nuclear Fusion

Question 13

What happens in Nuclear Fusion?

Answer 13

Hydrogen nuclei are jammed together so hard that they combine in pairs to form the element Helium, this process releases loads of energy

Question 14

What chemicals were made in stars?

Answer 14

All chemical elements with atoms heavier than helium

Question 15

How are the rest of the chemicals made?

Answer 15

Nuclear fusion can make elements as heavy as hydrogen with right enough densities. At the end of a star when it explodes during a supernova.

Question 16

Why is the fate of the universe difficult to predict?

Answer 16

We can only measure the mass of those parts in the universe which emit radiation
Precise measurements of the speed and distances of galaxies is difficult their radiation travels such a long way to get to us

Question 17

How do rocks provide evidence for the changes in Earth?

Answer 17

Erosion, sedimentation, fossils and folding

Question 18

What stops continents being worn down to sea level?

Answer 18

Mountains being continuously formed

Question 19

How can we see the past of the Earth?

Answer 19

Through its rocks and and the different layers in them

Question 20

How can the age of the Earth be estimated?

Answer 20

From its oldest rocks which are 4000 million years old

Question 21

What was the evidence for Wegners theory of continental drift?

Answer 21

Continents fit well together like a jigsaw
Similar fossils and rocks are found on continents now separated by oceans
Matching rock formations and mountain chains found on different continents

Question 22

How does Wegener’s theory explain the folding of rock into mountain ranges

Answer 22

Collisions between moving continents

Question 23

Why was Wegener’s theory rejected?

Answer 23

There was already similar explantations for some of his observations
Nobody could explain or measure the movements of the continents
Wegener was not a geologist
It was too big of an idea from limited evidence

Question 24

What is sea floor spreading caused by?

Answer 24

It is caused by continents moving because they sit on on the mantle, whose rocks move slowly by connection as they carry heat away from the Earths hot core

Question 25

How much does the sea floor spread by each year?

Answer 25

A few centimetres

Question 26

Why is there a pattern of magnetisation of sea floor rocks on other side of the oceanic ridges

Answer 26

Oceanic ridges from the expanding seafloor where liquid rock from the mantle fills the gap
The solidifying rock in the oceanic ridge is magnetised by the Earths field
The Earths magnetic field changes direction over millions of years
Each time the Earths field reverses, so does the magnetisation of the oceanic ridges
So the seafloor has strips of reversed magnetism parallel to where new rock is created

Question 27

How do volcanoes occur?

Answer 27

When liquid magma of forced through cracks where tectonic plates are moving apart

Question 28

How do volcanic mountains occur?

Answer 28

When on tectonic plate if forced under another heading towards it

Question 29

How do fold mountains occur?

Answer 29

When two tectonic plates meet head on

Question 30

How do Earthquakes occur?

Answer 30

Earthquakes are a release of energy form tectonic plates sliding past each other

Question 31

What are P waves?

Answer 31

They move quickly through solid crust and liquid core they are longitudinal which mean the particles vibrate along the direction of the motion of the wave.

Question 32

What are S waves?

Answer 32

They only move through the solid crust an are transverse so the the particles vibrate at right angles to the direction of motion of the wave

Question 33

What is a wave?

Answer 33

A wave a disturbance caused by a vibrating source that transfers energy in the direction that the wave travels without transferring matter

Question 34

What is the frequency of waves?

Answer 34

Number of waves that are made by the source each second or how many pass through are particular point

Question 35

What is the height of the wave called?

Answer 35

Amplitude

Question 36

What is the distance called between two ripples of a wave?

Answer 36

Wavelength