Marina is staring at an optical illusion where he sees a version of the American flag that is colored green, yellow, and black.
When the flag is removed and she stares at a blank screen, she sees an afterimage of the flag that is red, white, and blue. Which theory best explains this illusion?
The reason why Marina sees the colour red, white and blue or the original colour of the American flag is that because of a phenomenon known as Afterimage. The retina in our eyes have mainly three receptors that are colour sensitive known as cones. These receptors can perceive the colour green, red and blue. Now when we look or stare at a particular colour for a long time, what happen is that our retina becomes tired and they ignore the colours that stared at. And now they work to form other colours at the retina just like the way when we produce other colour from the primary colour.
If the red receptor gets exhausted we will see the colour red. Likewise when we see the colour orange when we stare at the colour blue.
This explains the optical illusion of the American flag.
Applicable linear expansion equation: ΔL = αΔTL In which ΔL = change in length, α = Linear expansion coefficient of steel, ΔT = change in temperature, L = original length
Therefore, ΔL = 12*10^-6*(18.5-(-3))*1410 = 0.36378 m
