Observe,questions/hypothesis,experiment.
I'm pretty sure its Sankey Diagram.
(Edit: Turned Dankey to Sankey which is the proper name for the diagram)
Answer:
Explanation:
The net force on electron is electrostatic force between electron and proton in the nucleus .
Fc = 
This provides the centripetal force for the circular path of electron around the nucleus .
Centripetal force required = 
So


