Apackage falls off a truck that is moving at 30 m/s. neglecting air resistance, the horizontal speed of the package just before it hits the ground is: ) less than 30 m/s but larger than zero. b) more than 30 m/s. c) about 30 m/s. d) zero. e) more information is needed for an estimate.

Explanation:

A package falls off a truck that is moving at 30 m/s.

Initial horizontal velocity of package = 30 m/s

For a dropping object acceleration along vertical direction is acceleration due to gravity and acceleration along horizontal direction is zero.

Since acceleration along horizontal direction is zero horizontal velocity remains the same. It will not change.

So he horizontal speed of the package just before it hits the ground is 30 m/s.

Option C is the correct answer.

3. dark matter

empty space could also be a simple vacuum