Physics 5054 · O Level · Radiation

Radiation — practice question

Several solar panels are fitted on the roof of a house. They take energy from the Sun to produce electricity and also to heat water flowing through tubes within the panels.
(a(i))[1]

State how energy from the Sun passes through space on its way to Earth.

(a(ii))[2]

Explain the benefit of panels with a black surface.

(b(i))[2]

Calculate the electrical energy produced by the panels in one hour. A current of 15 A at a potential difference of 24 V is supplied.

(b(ii))[3]

During the same interval, 51 kg of cold water is pumped through the panels. Its temperature rises from $16\,^{\circ}\text{C}$ to $45\,^{\circ}\text{C}$. The specific heat capacity of water is $4200\,\text{J}\,\text{kg}^{-1}\,^{\circ}\text{C}^{-1}$. Calculate the increase in thermal energy of the water.

Worked solution & mark scheme

This 8-mark question has a full step-by-step worked solution and mark scheme. One marking point: infrared / light / radiation

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