High speed elevators function under two limitations: (1) the maximum magnitude of vertical…

High speed elevators function under two
limitations: (1) the maximum magnitude of vertical acceleration that a typical
human body can experience without discomfort is about 1 .2 m/s2, and
(2) the typical maximum speed attainable is about 9.0 m/s. You board an
elevator on a skyscraper’s ground floor and are transported 180 m above the
ground level in three steps: acceleration of magnitude 1.2 m/s2 from
rest to 9.0 m/s, followed by constant upward velocity of 9.0 m/s, then deceleration
of magnitude 1.2 m/s2 from 9.0 m/s to rest, (a) Determine the
elapsed time for each of these 3 stages. (b)
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High speed elevators function under two
limitations: (1) the maximum magnitude of vertical acceleration that a typical
human body can experience without discomfort is about 1 .2 m/s2, and
(2) the typical maximum speed attainable is about 9.0 m/s. You board an
elevator on a skyscraper’s ground floor and are transported 180 m above the
ground level in three steps: acceleration of magnitude 1.2 m/s2 from
rest to 9.0 m/s, followed by constant upward velocity of 9.0 m/s, then deceleration
of magnitude 1.2 m/s2 from 9.0 m/s to rest, (a) Determine the
elapsed time for each of these 3 stages. (b) Determine the change in the
magnitude of the normal force, expressed as a % of your normal weight during
each stage, (c) What fraction of the total transport time does the normal force
not equal the person’s weight?

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