I'm sorry this is kind of a long question. I've been staring at it for about an hour now and I have no clue where to even start. Thank you so much!!!!

Question

A student stands on a bathroom scale in an elevator at rest on the 64th floor of a building. The scale reads 836 N.

1) As the elevator moves up the scale reading increases to 936 N, then decreases back to 836 N. Find the acceleration of the elevator.

2) As the elevator approaches the 74th floor, the scale reading drops to 782 N. What is the acceleration of the elevator now?

3) Using the results from parts a and b, explain which change in velocity, starting or stopping, would take the longer time.

4) What changes would you expect in the scale reading on the ride back down?

Answer 1

1)as the elevator accelerates upward, the student's weight increases
f = m a ... w = m a = m (g + e)

2)the elevator decellerates to a stop, so the student's weight is less than normal...same equations as #1

3)the greater the CHANGE in weight, the greater the acceleration ... which means a faster change in velocity (less time)

4)at the start (when the elevator accelerates downward) the scale will be below normal
once the downward velocity is constant, the scale will read normal
as the elevator is stopping at the bottom, the scale will be above normal

Answer 2

Thank you so much!! Would you mind explaining what the equations mean in #1? I know that Force= Mass x Acceleration, but what was the other equation?

Answer 3

Sorry my friend and I are both working on this together haha :)

Answer 4

It's strange, though, that both Kaylen and Maya said EXACTLY the same thing in posts made just one minute apart.

Please use the same name for your posts.

Answer 5

A classic example of Dissociative Identity Disorder . Look that up. I remember a great movie "Sybil" in 1976 on this. Sally Field was a great actress.

Answer 6

I wouldn't trust a person with Dissociative Identity Disorder.