Sankey Diagrams and Efficiency | GCSE Physics Practice
Sankey diagrams are used to represent energy transfers and the efficiency of a system.
What does the width of the arrow represent in a Sankey diagram?
What is Sankey Diagrams and Efficiency | Practice?
"A type of flow diagram in which the width of the arrows is proportional to the flow rate of energy."
Which law states that energy cannot be created or destroyed?
Why can efficiency never be 100% in a mechanical system?
A 5 kg weight is lifted 2 metres. Calculate its GPE (g = 9.8).
Which formula is used to calculate kinetic energy?
Efficiency Flow
Width of arrows = Amount of energy/flow.
Straight arrows usually represent useful energy out.
Downward arrows usually represent wasted (dissipated) energy.
Total energy in = Useful energy out + Wasted energy out.
Graph Rule: If a Sankey diagram shows 100J in and 20J of waste, the useful energy arrow MUST be exactly 4 times wider than the waste arrow.
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