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chenying
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Homework Statement
An object of mass m = 3.5 kg hangs from the middle of a (massless) rope of length L =17 m, as the drawing illustrates. It is being pulled with tension T =55 N. Calculate the distance D by which the rope sags in the middle
Homework Equations
F[tex]_{net}[/tex] = ma
D = length of sagging rope
L/2 = 8.5 meters
The Attempt at a Solution
So, because the rope is being pulled with a tension of 55 N to keep the object at a certain distance, the tension throughout the string with the mass is 55 N.
I made theta my angle with the horizontal, which is the value I'm trying to find.
The mass is balanced out evenly in the middle, so the two y components of the rope (2Tsin[tex]\Theta[/tex]) would have to equal the weight of the mass, mg.
I have all the variables except for theta, so solving for theta, I get a value of 18.1688 degrees.
I have the length of the rope, 8.5 meters, and the angle, 18.1688 degrees, so I can use tan [tex]\Theta[/tex] = D/8.5
solving for D, I got 2.78954 meters, which was not right.
So, anyone has an idea what I did wrong or how my approach was incorrect?