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Ne4ueva [31]
3 years ago
7

PLEASE HELP... 100 POINTS....

Physics
1 answer:
kirill [66]3 years ago
6 0

Answer: 20 m/s in 2 significant figures.

Explanation:

Initial velocity (u) = 0 m/s

Acceleration by gravity (a) = 9.81 m/s^2

Displacement (s) = 20m

Final velocity (v) = ?

Now, use formula

v^2 = u^2 + 2 * a * s

or, v^2 = 0^2 + 2 * 9.81 * 20

or, v = square root of( 2 * 9.81 * 20 )

So, v = 20 m/s in 2 significant figures.

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