Consider the following experiment (which you can
actually perform): Obtain a spring scale such as a
typical bathroom scale, place it in an elevator, and
stand on it. Note the exact value when the elevator is at rest. Now ride up several floors. As the
elevator starts up, there is an acceleration upward.
Note how the reading on the spring scale changes.
Next ride down. When the elevator starts down,
note how the reading changes. Once the elevator
reaches a constant velocity up or down, note the
reading of the scale. What do you predict these
various readings would be?