Engineering Board Exam Reviewer · Engineering Mechanics · medium
An object is dropped from rest from a height of 20 m. Neglecting air resistance, how long does it take to hit the ground? (g = 9.81 m/s2)
- 2.04
- 1.43
- 2.02
- 4.04
Answer
C. 2.02
Solution
Using h = 1/2gt2: t = sqrt(2h/g) = sqrt(2(20)/9.81) = 2.02 s.
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