The height of the chairlift above the snow when the ski falls off is determined as 20.4 m.
The height of the chairlift is calculated from the principle of conservation of mechanical energy as shown below;
P.E = K.E
mgh = ¹/₂mv²
gh = ¹/₂v²
h = v²/2g
where;
h = (20)²/(2 x 9.8)
h = 20.4 m
Thus, the height of the chairlift above the snow when the ski falls off is determined as 20.4 m.
Learn more about conservation of energy here: https://brainly.com/question/24772394
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