Question

Now, three masses (m1 = 3.1 kg, m2 = 9.3 kg and m3 = 6.2) hang from three identical springs in a motionless elevator. The springs all have the same spring constant given above.
Now the elevator is moving downward with a velocity of v = -2.9 m/s but accelerating upward at an acceleration of a = 3.6 m/s2. (Note: an upward acceleration when the elevator is moving down means the elevator is slowing down.) the masses hang in series with one another m3 is on the bottom and m1 is on the top
What is the distance the lower spring is extended from its unstretched length?

Answer 1

somebody please help me

Answer 2

See my comment below. I wonder if they mean net SPRING force ignoring gravity. 208 up - 83.1 down

Answer 3

if I wanted to find the lower spring extended from it's unstretched length, what is a formula that I could use? I found that the distance the middle spring is stretched from its equilibrium length is 44.9cm, would I have to use this as well?

Answer 4

You only need the force in that one spring 83.1 N = k * stretch
HOWEVER if you want the change in position from the ceiling
you must do stretch 1 + stretch 2 + stretch 3
Did they ask for the total distance or just the change in length of that spring?

Answer 5

they weren't very specific with that, the exact wording is the question I posted above