A single mass m1 = 4.5 kg hangs from a spring in a motionless elevator. The spring is extended x = 15 cm from its unstretched length.
Ā
1)What is the spring constant of the spring?
Ā
Now, three masses m1 = 4.5 kg, m2 = 13.5 kg and m3 = 9 kg hang from three identical springs in a motionless elevator. The springs all have the same spring constant that you just calculated above.
Ā
2)What is the force the top spring exerts on the top mass?
Ā
3)What is the distance the lower spring is stretched from its equilibrium length?
Ā
4)Now the elevator is moving downward with a velocity of v = -2 m/s but accelerating upward with an acceleration of a = 3.8 m/s2. (Note: an upward acceleration when the elevator is moving down means the elevator is slowing down.)
Ā
What is the force the bottom spring exerts on the bottom mass?
Ā
5) What is the distance the upper spring is extended from its unstretched length?
Ā
6) Finally, the elevator is moving downward with a velocity of v = -2.5 m/s and also accelerating downward at an acceleration of a = -2.2 m/s2.
Ā
The elevator is:
Ā
speeding up
Ā
slowing down
Ā
moving at a constant speed
Ā
7) Rank the distances the springs are extended from their unstretched lengths:
Ā
x1 = x2 = x3
Ā
x1 > x2 > x3
Ā
x1 < x2 < x3
Ā
8) What is the distance the middle spring is extended from its unstretched length?