Answer:
The amount of energy wasted by light bulb 2 = 70 J
Explanation:
Sankey diagrams are used to graphically indicate the proportional flow rate of a quantity
The labelled Sankey diagrams, here, indicate the energy transfers in two light bulbs, light bulb 1 and light bulb 2
From the labelled Sankey diagrams, we have;
For light bulb 1, the input energy = 80 J
The useful energy = 40 J
The wasted energy = 80 - 40 = 40 J
For light bulb 2, the input energy = 80 J
The useful energy = 10 J
Therefore, the wasted energy = 80 - 10 = 70 J
The amount of energy wasted by light bulb 2 = 70 J.
