PLEASE HELP!! A box falls out of an airplane that is traveling horizontally at 100m/s. The plane is at an altitude of 300m.
Where does the box land relative to where it was dropped from?

Explanation:

Key point: the vertical motion is free fall, the horizontal motion remains at uniform speed of 100 m/s (because there is no force in the horizontal direction if we neglect air resistance.)

The time of free fall can be calculated first:

h = 1/2 g t^2 => t = sqrt(2 h /g) = sqrt(2 * 300 m / 9.81 s) = 7.82 seconds.

In that time, the horizontal displacement will be

s = v_horizontal * t = 100 m/s * 7.82 s = 782 m.

So the box will land 782 m further than the point it was dropped from (and 300 m lower of course)

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