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Billy drops a water balloon from the roof of his house. Since the balloon began with an original velocity of zero, how far above ground was the balloon dropped if it took 2.5 seconds to hit the ground?

A. 30.6 m
B. 122.5 m
C. 12.3 m
D. 49.0 m

User Amelie
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2 Answers

4 votes
The balloon was 30.65 meters above ground.

ANSWER: A
User Yer
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7.6k points
5 votes

Answer: The correct answer is option (A).

Step-by-step explanation:

Initial velocity of the balloon = 0 m/s

let the distance covered by the balloon from roof to the ground= h

Time taken by the balloon to reach the ground = t = 2.5 seconds

Acceleration due to gravity = g =9.8
m/s^2

Using confuse equation of the motion:


h=ut+(1)/(2)gt^2


h=0 m/s* 2.5 s+(1)/(2)*9.8 m/s^2* (2.5 s)^2=30.625 m\approx 30.6 m

Hence, the correct answer is option (A).

User Tushar Shukla
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7.7k points