Quelpr
9 marksFirst Law of Thermodynamics

CAPE Physics Unit 1 · 2002 · Paper 2 · Question 8(b)(ii)

126 J of heat is supplied to the gas at C via the copper rod at B. 90 J of the energy supplied to the gas is used up as work done by the gas to push back the piston.

Why is the actual value for the change of internal energy of the gas at C lower than the value you calculated in (b)(i) above.

The mark scheme is shown once you've answered.

Practise this question

Other parts of this question

  1. 8(a)(i)Name the process by which heat is supplied to the gas at C via the copper rod at B.[8 marks]
  2. 8(a)(ii)Use the kinetic theory to explain why the piston at D eventually pushes on the switch at E.[8 marks]
  3. 8(a)(iii)Why must the copper rod be lagged and the piston light and frictionless?[8 marks]
  4. 8(b)(i)Calculate an estimate for the change of internal energy of the gas at C.[9 marks]
  5. 8(b)(iii)a)Calculate the number of moles of helium atoms in the container.[9 marks]
  6. 8(b)(iii)b)Calculate the total kinetic energy of the helium atoms.[9 marks]
  7. 8(c)Explain what happens to the piston at D and why.[3 marks]

More practice: the rest of this paper · more First Law of Thermodynamics questions · all CAPE Physics Unit 1 past papers