CSEC Physics · January 2010 · Paper 2 · Question 4(b)(ii)

A solar water heater system consists of a solar collector of area 5 m², a storage tank, and connecting pipes, as shown in Figure 4. The average solar radiation incident on Castries, St. Lucia is 5 kWhm⁻² per day, and the collector absorbs 95% of the solar radiation incident on it.

Calculate how much energy per day can be used to heat water if the collector emits 50% of the heat energy it receives from the atmosphere.

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