Video Transcript
Which of the following
statements comparing position, distance, and displacement is correct? An object may record a nonzero
distance while recording a displacement of zero. An object may record a distance
of zero while recording a nonzero displacement. An object may record a nonzero
distance while maintaining a position of zero. An object may record a nonzero
displacement while maintaining a position of zero.
In this exercise, we want to
evaluate each of these four statements and find which one of the four is
correct. Let’s begin with the first
statement. An object may record a nonzero
distance while recording a displacement of zero. That’s accurate. We can imagine an object moving
in such a way that it starts and ends at the same location. And yet, it’s travelled a total
distance in order to complete that journey. In that case, its distance
travelled would indeed be nonzero. But its displacement, that is
the separation from its start and end point, would be zero. We highlight this first
statement as correct. Even though we know this is the
right one, let’s continue on and look at the remaining statements. The second statement says that
an object may record a distance of zero while recording a nonzero
displacement. We know this statement can’t be
accurate because distance is always equal to or greater than displacement.
The third statement says that
an object may record nonzero distance while maintaining a position of zero. If an object maintains a
position of zero, that means that it doesn’t move at all. In which case, it couldn’t
record a nonzero distance. So we know this third statement
is not accurate either. And finally, the fourth
statement says an object may record a nonzero displacement while maintaining a
position of zero. Once again, if an object
maintains a position of zero, then its displacement as well as its distance
cannot be anything other than zero. This means it’s unable to
record a nonzero displacement. So this fourth statement is not
correct either.