8463/1H June 2021

  • Energy from the Sun is released by nuclear fusion.

i-​​ Complete the sentences.

[2 marks]

Nuclear fusion is the joining together of ______________________ .

During nuclear fusion the​​ total mass of the particles ________________ .

 

ANSWER

Nuclear fusion is the joining together of​​ nuclei.

During nuclear fusion the total mass of the particles​​ decreases.

 

ii-​​ Nuclear fusion of deuterium is difficult to achieve on Earth because of the high​​ temperature needed.

Electricity is used to increase the temperature of 4.0 g of deuterium by 50 000 000 °C.

specific heat capacity of deuterium = 5200 J/kg °C

Calculate the energy needed to increase the temperature of the deuterium by 50 000 000 °C.

Use the Physics Equation Sheet.

[3 marks]

SOLUTION

E=mcθ

E=0.004×5200×50,000,000

E=1.04×109 J

iii-​​ The idea of obtaining power from nuclear fusion was investigated using models.​​ 

The models were tested before starting to build the first commercial nuclear fusion power station.

Suggest two reasons why​​ models were tested.

[2 marks]

ANSWER

  • To assess safety risks in the experiment.

  • To assess the efficiency of the nuclear fusion process.​​ 

  • To predict the possible results and outcomes.

  • To develop a better understanding of the process.​​ 

(You may pick any two​​ of the reasons.)

 

iv-​​ Generating electricity using nuclear fusion will have fewer environmental effects than generating electricity using fossil fuels. Explain one environmental effect of generating electricity using fossil fuels.

[2 marks]

ANSWER

  • Fossil fuels release green house gases such as CO2​​ , SO2,​​ etc, which causes global warming.

  • Toxic gases (SO2) produced during the burning of fossil fuel combines with​​ rain​​ and produces acid rain.​​