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GCSE level questions on the Earth in Space

Q10.The lifecycle of some stars includes a supernova stage.

(a)

(i) What happens to a star during the supernova stage?

It explodes.

[1 mark]

(ii) After the supernova stage either a black hole or a neutron star will be formed. What is the missing word?

 

[1 mark]

(iii) The lifecycle of the Sun will not include a supernova stage. Give the reason why.

It is not massive enough.

[1 mark]

 

(b) Describe what happens to a star like the Sun as it passes through its lifecycle. Your answer should include how the star was formed and the names of the stages the star passes through.

This type of question is marked in two ways:

- the examiner looks for relevant points

- but also for a logical sequence...

It is not just a 'tick fest' - but a marker does look to see how many relevant points you have made, then considers how you have strung them together to put your answer into a 'level'

Level 3:

There is a clear description of what happens to a star like the Sun as it passes through its lifecycle

and

at least three stages are named in the correct order.
5 - 6 marks
Level 2:

There are basic descriptions of what happens to a star like the Sun as it passes through its lifecycle

and

at least two stages are correctly named and are in the correct order.
3 - 4 marks
Level 1:

There is a basic description of what happens to a star like the Sun as it passes through its lifecycle

or

at least two stages are correctly named and are in the correct order.
1 - 2 marks
Level 0:

No relevant information
0 marks

 

Examples of physics points that should be made in the response:

A nebula of dust and gas/hydrogen (from space) is pulled together by the force of gravitational attraction to form a protostar.
temperature increases and hydrogen starts to convert to helium by the process of nuclear fusion as it becomes a stable main sequence star
(the core of the) star runs out of hydrogen and the star expands (to become) a red giant
heavier elements (up to iron) are formed (by fusion) and the star shrinks (to become) a white dwarf
the star cools/fades, eventually stopping emitting energy/radiation and becomes a black dwarf

[6 marks]

(c) There are a number of theories about how the Universe will end. A recent theory suggests that 22 billion years from now the Universe will rip itself apart.

Suggest why scientists may support one particular theory and reject others.

Scientists tend to support a theory if there is evidence/data known that can only be explained by that one theory, or that has been predicted by one particular theory. They may reject a theory if it cannot explain gathered evidence or has predicted something that turns out to be false.

Theories supported/provided by famous/respected scientists tend to be respected until proved false. Those from unknown sources are looked at with more suspicion.

[2 marks]

(Total 11 marks)