To achieve a speed of 2 m/s, the bottle must be dropped at m. to achieve a speed of 3 m/s, the bottle must be dropped at m. to achieve a speed of 4 m/s, the bottle must be dropped at m. to achieve a speed of 5 m/s, the bottle must be dropped at m. to achieve a speed of 6 m/s, the bottle must be dropped at m.

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Assumptions:

Explanation:

Consider the "SUVAT" equation

,

where

For example, if the bottle needs to achieve a speed of by the time it reaches the ground,

Apply the previous equation to find the minimum height, :

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Replace the value and apply the formula to find the minimum height required to reach different final speeds.

snell's law

refractve index = sin incidence / sin refraction