Question

The formula v=√64h can be used to find the velocity v in feet per second of an object that has fallen h feet. Find the velocity of an object that has fallen 30 feet. Round your answer to the nearest hundredth.

A) 960 feet/sec
B) 43.82 feet/sec
C) 240 feet/sec
D) 350.54 feet/sec

Answer 1

B) 43.82 feet/sec

Explanation:

Fill in the number and evaluate:

v = √(64×30) = √1920 ≈ 43.82 . . . . ft/s

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Of course, √(64h) can be simplified to 8√h. You know that √30 lies between 5 and 6, so the velocity lies between 8·5 = 40 and 8·6 = 48. There is only one answer choice in that range.