Tension in Cables Supporting a Watermelon on Scaffolding

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The discussion revolves around calculating the tension in two cables supporting a 6.1m scaffolding with an 8.9kg watermelon at one end. Participants emphasize the importance of equilibrium, stating that the sum of vertical forces and torques must equal zero. The correct approach involves converting the watermelon’s weight into Newtons and applying torque equations to find the tensions in the cables. Clarifications are provided regarding the proper use of units and the relationships between the forces. The conversation concludes with participants expressing gratitude for the assistance in solving the problem.
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An 8.9kg watermelon is placed at one end of a 6.1m, 238 N scaffolding supported by two cables. One supporting cable is at the opposite end of the scaffolding, and the other is 0.76 m from the watermelon. The acceleration of gravity is 9.8 m/s^2.

How much tension is in the cable at the end of the scaffolding?
How much tension is in the cable closest to the watermelon?

I really have no clue how to go about this. Any relevant formulas I should know?
 
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The system is in equilibrium. Sum of forces in y direction and sum of torques about any point must equal zero. Don't forget the torque from the scaffolding .
 
For equilibrium of a body:
1. ΣF = 0
2. ΣT = 0
where, F is the force and T is the torque.
(bold ones are vector quantities.)
 
ok well with the watermelon converted over to N I've got a total of 325.28N * 9.8m/s^2 = 3187.744 for my downward force. If that is correct then how do I apply the distance from the melon to figure the tension on the individual cables?
 
galuda said:
ok well with the watermelon converted over to N I've got a total of 325.28N * 9.8m/s^2 = 3187.744 for my downward force. If that is correct then how do I apply the distance from the melon to figure the tension on the individual cables?

Remember: Always try to be atleast dimensionally correct!
How come, "325.28N * 9.8m/s^2 = 3187.744 for my downward force"?? You must be knowing, unit of force is N.. then how, N * m/s^2 = N??
In fact, if tensions in the strings are T1 and T2, then
T1 + T2 = 238N + 8.9kg*9.8m/s^2 = 325.22N.

Now, take torque about any point and equate to zero to get one more equation involving T1 and/or T2. Then, solve for T1 and T2 from the two equations obtained. It would be quicker if you take torque about the point where the cable meets scaffolding (either of them).
 
ah ok sorry about that. Thank yall very much for the assistance.
 
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