Video Transcript
Fill in the blanks. A ball is dropped from a tall
building. As the ball falls, it has uniform
blank while its blank increases. Is it (A) speed and distance, (B)
speed and acceleration, or (C) acceleration and speed?
A ball is dropped from a tall
building. The ball is dropped. The ball is not thrown
downward. The ball is just released and
allowed to fall. At the moment the ball is released,
the ball’s initial speed is zero. The ball falls to the ground, so
the ball must increase its speed from zero. The speed of the ball cannot be
constant, it cannot be uniform.
Looking at the options, option (A)
and option (B) both fill the first blank with the word speed. Choosing option (A) or option (B)
means stating that as the ball falls, it has uniform speed. And we have just shown that this is
not true. Option (C) fills the second blank
with the word speed. Choosing options (C) means stating
that as the ball falls, it has increasing speed. We have just shown that this is
true.
As option (C) fills the first blank
with the word acceleration, choosing option (C) means stating that as the ball
falls, it has uniform acceleration. The ball falls because the weight
of the ball accelerates the ball. We know the weight of the ball is
constant, so the acceleration of the ball due to its weight is also constant or
uniform. We see that option (C) is correct
for both the first and second blanks. A ball is dropped from a tall
building. As the ball falls, it has uniform
acceleration while its speed increases.
