You observe water sloshing up and down in a U-shaped tube as it set in motion with a force.
The motion starts when a plunger is raised in the left side of the tube. This creates a partial vacuum and the water rises on the left side and lowers on the right side. When the plunger is pulled out of the tube, the water on the left side falls under the influence of gravity and the water on the right side rises.
What evidence can you cite to justify that the motion is simple harmonic motion?
Select TWO answers.