1. Grade 6 Science Unit 11 Energy
Energy Arrows
Grade 6 Science
Unit 11 Energy

2. Learning Objectives To

3. Energy arrow for a filament bulb
9 J
wasted
energy
out
10 J energy in
1 J
useful
energy
out

4. Energy arrow for a filament bulb
9 J
wasted
energy
out
10 J energy in
1 J
useful
energy
out
6 J
wasted
energy
out
Sankey Diagram for an energy efficient bulb
10 J energy in
4 J
useful
energy
out

5. Why are they also called Sankey Diagrams?
Captain Matthew Henry Phineas Riall Sankey was an engineer.
In 1898 he was the first person to publish a diagram that used the width of an arrow to show the size of the energy flow.
The first ever Sankey diagram shows the energy flow in a real steam engine compared with a ‘perfect’ engine.
Sankey diagrams are so useful that you can buy computer programs to draw them!
Captain Henry Sankey (1853 – 1925)

6. Plenary