# Min weight of elevator accelerating, constant velocity, decelerating

1. Jun 19, 2013

### judas_priest

1. The problem statement, all variables and given/known data

Starting from rest, an elevator accelerates uniformly between the 1st and 2nd floors, and decelerates uniformly between the 5th and 6th floors, coming to a stop at the 6th floor. Between the 2nd and 5th floors, the elevator covers the 6 meter distance between each two adjacent floors in 1 second. Inside, Liz (who is about to graduate) is standing on a scale that reads 800 N when the elevator isn't moving. What was her minimum scale reading during the trip? Use g = 10 m/s^2.

2. Relevant equations

3. The attempt at a solution

From 1st floor to second floor the equation would be $$N + Ma = Mg.$$
From second floor to fifth, it moves with constant velocity i.e 6 m/s
From fifth to sixth, the equation would be $$N - Ma= Mg.$$

Here, from the given data in question M = 8kgs.
How do I find the minimum reading?

2. Jun 19, 2013

### judas_priest

Never mind. Was making a silly mistake. Got it.