Quelpr
6 marksConservation of Energy

CAPE Physics Unit 1 · 2012 · Paper 2 · Question 6(c)(i)

Figure 3 shows an electric water heater designed to provide a continuous supply of hot water. Water is flowing at the rate of 0.300 kg min⁻¹, the inlet thermometer registers 20.0°C, the voltmeter reads 120 V and the ammeter reads 10.0 A.

Calculate the power developed by the heater.

This question uses a figure or table from the paper — you'll see it when you practise.

The mark scheme is shown once you've answered.

Practise this question

Other parts of this question

  1. 6(a)(i)Describe how a physical property of a substance which varies with temperature may be used for the measurement of temperature on an empirical centigrade scale.[6 marks]
  2. 6(a)(ii)Explain how the absolute thermodynamic scale of temperature differs from that described above.[1 mark]
  3. 6(a)(iii)State ONE reason why mercury is still often used in thermometers.[1 mark]
  4. 6(b)(i)Determine the new temperature of the bath, as measured using the resistance thermometer.[3 marks]
  5. 6(b)(ii)Suggest ONE reason for the difference between this reading and the value calculated above in b (i).[1 mark]
  6. 6(c)(ii)When a steady state is finally reached, what is the reading on the outlet thermometer?[1 mark]
  7. 6(c)(iii)State ONE reason why it is NOT necessary to take into account the heat capacity of the apparatus itself.[1 mark]

More practice: the rest of this paper · more Conservation of Energy questions · all CAPE Physics Unit 1 past papers