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Marjorie drops an object from a height of h meters, and it hits the ground with a velocity of v m/s, as given by the function v equals the square root of 19.6 h. If the velocity of the object is 68.6 m/s, what was the height of the object before it was dropped? Round your answer to the nearest tenth.

User Gignu
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1 Answer

17 votes
17 votes

Answer:

240.1 m

Step-by-step explanation:

Potential energy ( mgh) is fully converted to Kintetic energy ( 1/2 mv^2)

equate them

mgh = 1/2 mv^2 divide by 'm'

gh = 1/2 v^2

9.8 h = 1/2 v^2

19.6 h = v^2 v = sqrt ( 19.6h) (as given)

68.6 = sqrt (19.6 h) solve for h = 240.1 m

User Hugh
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