Stellar Evolution (Edexcel IGCSE Science (Double Award): Physics)

The diagram shows some incomplete notes about a stellar process. An astronomer left the notes to a colleague for them to decipher. 

Identify the process described in the diagram.

The colleague wants to include some extra detail in stage 3.

Which of the following correctly describes the physical process outlined in stage 3 and the 'smaller nuclei' and 'bigger nuclei' that are mentioned? 

The longest stage in this process is

(i) State the name given to the star in stage 4.

[1]  

(ii) Explain what happens in stage 4.

[3]

The colour of visible light a star emits tells us how hot or cold it is.

The table contains the colour classifications of the visible light emitted from stars. 

 Place a number from 1 − 7 in each box to put them in order from hottest (1) to coolest (7).

(i) Identify and explain the coolest stage of a star's life cycle.

[2]  

(ii) Identify and explain the final stage and colour in the life cycle of a star similar in size to the Sun.

(3)

Explain how stars like the Sun are formed.

Most of the stars in the universe are main sequence stars, including the sun. 

Describe the similarities between main sequence stars.

The table gives some statements about the relationship between a star's colour and its surface temperature. 

 Add ticks (✓) to the table to show which two statements are correct.

The table shows the colour and surface temperature of several known stars.

(i) Identify a star with a temperature of 7000 K.

[1]

(ii) Identify a star with a temperature of 2000 K.

[1]

(iii) State and explain which of the stars you identified is likely to be the largest.

[2]

The table shows the 5 stages of the life cycle of a star that has a similar mass to the Sun. 

 (i) State and explain what happens in stage 2 of the diagram.  

Include specific references to the relationships between

• the masses of the bodies involved and the forces acting between them

• the separation of the bodies involved and the forces acting between them

[4]

(ii) State and explain what happens in stage 4 of the diagram.

[4]

The timescale of stage 3 is in the order of

Explain why the star remains stable during stage 3 for the length of time you selected in part (b).

For stars with much larger masses than our Sun, stages 1 to 3 are almost exactly the same as lower mass stars. For the later stages, 4 and 5, the processes begin to differ.

Compare and contrast the final two stages in stars with much larger masses than our Sun and stars with similar masses to our Sun.

The table contains information on the mass of different stars.

 (i) Compare the masses of Proxima Centauri and VY Canis Majoris to the Sun.

[1]

(ii) Explain how these differences will affect the time these stars can remain stable.

[3]

Describe what will happen to each of the stars after they leave the main sequence stage.