... as the heat energy emitted by the bulb is absorbed by the water. The light energy is very small and hence is difficult to measure it directly. So it shall be measured it by subtracting the heat energy given out from the total input energy. The light bulb is submerged in 0.2kg water, and turned on for 900 seconds. The current and voltage of the electrical supply is noted and a table is made with initial findings. Circuit diagram of the experiment The law of conservation of energy states that energy may neither be created nor destroyed. Therefore the sum of all the energies in the system is a constant. So the energy input is equal to the energy output. I.e. Electrical energy = Heat energy + Light energy The results obtained are shown below Current(A) Voltage(V) Initial water temperature( (c)) Temperature after 900 sec(c) 1 3.0 17.0 20.0 1.1 4.4 17.0 21.0 1.3 6.0 17.0 22.5 1.4 7.2 17.0 24.0 1.6 8.5 17.0 26.0 1.8 10.9 17.0 29.0 2.1 12.0 17.0 32.0 2.3 13.2 17.0 33.0 These results were collected, so that I can measure any quantities from this data ...

See this essay or coursework document in full right now