AQA A Level Physics Paper 2 2019 Question Paper

Section A Answer all questions in this section. 0 1 Figure 1 shows a perfectly insulated cylinder containing 0.050 kg of liquid nitrogen at a temperature of 70 K. A heater transfers energy at a constant rate of 12 W to the nitrogen. A piston maintains the pressure at 1.0 × 105 Pa during the heating process. Figure 1 Do not write outside the box S - The Marketplace for Revision Notes & Study Guides Downloaded by: jessicaonyebuchi | Distribution of this document is illegal S - The Marketplace for Revision Notes & Study Guides 3 *03* Turn over ► IB/M/Jun19/7408/2 Do not write outside the 0 1 box . 1 The nitrogen is heated from 70 K and is completely turned into a gas after 890 s. Calculate the specific heat capacity of liquid nitrogen. Give an appropriate unit for your answer. specific latent heat of vaporisation of nitrogen = 2.0 × 105 J kg−1 boiling point of nitrogen = 77 K [5 marks] specific heat capacity = unit = Question 1 continues on the next page S - The Marketplace for Revision Notes & Study Guides Downloaded by: jessicaonyebuchi | Distribution of this document is illegal S - The Marketplace for Revision Notes & Study Guides 4 *04* IB/M/Jun19/7408/2 Do not write outside the 0 1 box . 2 The work done by the nitrogen in the cylinder when expanding due to a change of state is X. The energy required to change the state of the nitrogen from a liquid to a gas is Y. Deduce which is greater, X or Y. density of liquid nitrogen at its boiling temperature = 810 kg m−3 density of nitrogen gas at its boiling temperature = 3.8 kg m−3 [4 marks] 9 S - The Marketplace for Revision Notes & Study Guides Downloaded by: jessicaonyebuchi | Distribution of this document is illegal S - The Marketplace for Revision Notes & Study Guides 5 *05* Turn over ► IB/M/Jun19/7408/2 Do not write outside the 0 2 box . 1 State what is meant by the internal energy of a gas. [2 marks]