Katie is at Niagara Falls,staring at the downward rush of the water for several seconds.When she then looks at the nearby trees and rocks,they will seem to be:
A)moving upward.
B)moving downward.
C)moving sideways.
D)oscillating upward and downward.

Question

Quizplus · Accepted Answer

This is an example of the waterfall illusion, where your brain has adapted to the downwards motion of the waterfall and perceives stationary objects as moving upwards.

Katie Is at Niagara Falls,staring at the Downward Rush of the Water