Answer:
We have learned that refraction occurs as light passes across the boundary between two media. Refraction is merely one of several possible boundary behaviors by which a light wave could behave when it encounters a new medium or an obstacle in its path.
The time of motion of the track star is determined as 0.837 s.
<h3>Time of motion of the track star</h3>
The time of motion of the track star is calculated as follows;
T = (2u sinθ)/g
where;
- T is time of motion
- g is acceleration due to gravity
- θ is angle of projection
T = (2 x 12 x sin20)/9.8
T = 0.837 s
Learn more about time of motion here: brainly.com/question/2364404
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