 #1
 43
 5
Homework Statement
Block B hangs from Block A by a Rope 1. Rope 2 hangs below Block B.
Each block has a mass of 1.0 kg.
Each rope has a mass of 250 g.
The entire assembly is accelerating upward at 3.00 m/s^2 by force F.
A. What is F?
B. What is the tension at the top of Rope 1?
C. What is the tension at the bottom of Rope 1?
D. What is the tension at the top of Rope 2?
Homework Equations
F = ma
T = Sum(forces acting on that point)
The tension force at any point in the system = sum of forces acting at that point.
The Attempt at a Solution
The total mass of the system is 2 x 1000 g + 2 x 250 g = 2500 g
The net acceleration on the entire system = 3.00 m/s^2. So the force at any point is that acceleration x the mass below that point.
A. F = ma = 2500 g x 3.00 m/s^2 = 7500 gm/s^2 = 7.4 N
B. F = ma = (250 g + 1000 g + 250 g) x 3.00 m/s^2 = 4500 gm/s^2 = 4.5 N
C. F = ma = (1000 g + 250 g) x 3.00 m/s^2 = 3750 gm/s^2 = 3.75 N
D. F = ma = 250 g x 3.00 m/s^2 = 750 gm/s^2 = 0.75 N
And the tension on the bottom of Rope 2 = 0 N.
Did I get that right?
Attachments

13.9 KB Views: 1,044
Last edited: