A first object is thrown vertically upward with some initial speed and some initial height above the ground. Simultaneously, a second object is thrown straight down with the same initial speed and same initial height above the ground. Before the second object reaches the ground, the distance between the two objects _______as time advances. Ignore air resistance.

Question

a)stays the same
b)increases than decrease
c)cannot by determined (not enough info.)
d)increases at an increasing rate
e)increases at a constant rate

Answer 1

The height y1 of the first object from the initial position, y0 with respect to time is given by the equation:
y1=ut-(1/2)gt²

Similarly, the height y2 of the second object is given by:
y2=-ut - (1/2)gt²

where
g=acceleration due to gravity, and
u=initial speed

The distance between the two objects is therefore given by y1-y2
=2ut
which is a linear function of time.

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