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physics_newb
Nov16-09, 05:58 AM
1. The problem statement, all variables and given/known data
If the balloon in the diagram drawn below is accelerating upwards at 0.40 m/s2, calculate the tension in each piece of rope. Assume that the rope has no mass.
http://img261.imageshack.us/img261/964/capture2gm.png
http://img261.imageshack.us/img261/964/capture2gm.png


2. Relevant equations
a=0.40m/s^2
m=15kg
g=9.8m/s^2
F_t=?
F_g=?


3. The attempt at a solution
Rope 1

Step1
If the balloon in the diagram drawn below is accelerating upwards at 0.40 m/s2, calculate the tension in each piece of rope. Assume that the rope has no mass.





















Rope 1
a=0.40m/s^2
m=15kg
g=9.80m/s^2
F_t=?
F_g=?
Step1
F_g=mg
F_g=15*9.8
F_g=147m/s^2
Step2
Fnet=m*a
Fnet=F_g+F_t
15*0.40=147+F_t
6=147+F_t
6-147=F_t
-141.0N=F_t
Rope 2
a=0.40m/s^2
m=9kg
g=9.80m/s^2
F_t=?
F_g=?




Step1
F_g=mg
F_g=9*9.8
F_g=88.2m/s^2
Step2
Fnet=m*a
Fnet=F_g+F_t
9*0.40=188.2+F_t
3.6=88.2+F_t
3.6-88.2=F_t
-84.6N=F_t

Therefore the tension on rope 1 is -141.0N
Therefore the tension on rope 2 is -84.6N

physics_newb
Nov16-09, 06:15 AM
is this right now?