- #1

- 6

- 0

1. Assume you are on a planet similar to earth where the acceleration of gravity is 10m/s^2 and the positive directions for displacement velocity and acceleration are upward. At t=0sec., an elevator is at a displacement of x=0 with a velocity of v=0m/s. A student whose weight is 400N stands on a scale in an elevator and records the scale reading as a function of time. The data is shown below:

0-5s--------400N

5-10s-------500N

10-15s------600N

15-20s-----0N

a) Which direction is the force due to the scale?

b) What is the mass of the student?

c) Calculate the acceleration of the elevator during the 15-20s interval.

d) Draw the a vs. t graph.

e) What is the velocity of the elevator at t=20s?

f) Draw the v vs. t graph.

g) What is the displacement of the elevator above the starting point at the end of 20s?

h) Draw the d vs. t graph.

I was only completely sure about a and b, for a the direction is up and for b the mass is 40kg. I obviously don't want just answers, but steps and hopefully explainations to go along with it.

Thank you.