Newtonian Mechanics/Forces Question

AI Thread Summary
The discussion centers on calculating the tensions in two cords suspending buckets, each weighing 3.5 kg. Initially, the user understands the force diagrams but struggles with how upward acceleration affects tension. It is clarified that the upward force is mediated by the tension in the cords, which increases when the system accelerates upward. The user realizes that the applied force is not external but rather the result of the tension itself, leading to increased tension in both cords. Ultimately, the user expresses gratitude for the clarification and acknowledges their understanding.
MyNameIsNicholas
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These buckets are being suspended. The cords have no mass and each bucket is 3.5 kg.

a.) Find the tension in the upper cord (T1) and the lower cord (T2)
b.) If the apparatus is pulled upwards from the top of the upper cord, what are the new tensions of each cord?

I understand the first part. The force diagrams consist of:
(Upper Bucket): T1 upwards, T2 downwards, and Fg downwards
(Lower Bucket): T2 upwards and Fg downwards

However, when the apparatus accelerates upwards, the tensions in both cords increases. This makes sense physically but in the force diagram isn't force applied (causing acceleration) going upwards? And if that were the case, then force applied would counter-intuitively decrease the tension within the cords. Can someone graciously clear this up for me?
 
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Newton's second law applies to each bucket independently.
 
MyNameIsNicholas said:
4_41.gif


These buckets are being suspended. The cords have no mass and each bucket is 3.5 kg.

a.) Find the tension in the upper cord (T1) and the lower cord (T2)
b.) If the apparatus is pulled upwards from the top of the upper cord, what are the new tensions of each cord?

I understand the first part. The force diagrams consist of:
(Upper Bucket): T1 upwards, T2 downwards, and Fg downwards
(Lower Bucket): T2 upwards and Fg downwards

However, when the apparatus accelerates upwards, the tensions in both cords increases. This makes sense physically but in the force diagram isn't force applied (causing acceleration) going upwards? And if that were the case, then force applied would counter-intuitively decrease the tension within the cords. Can someone graciously clear this up for me?
I'm not sure why you would believe that's the case, but look at ##\sum F = ma##. Solve for the tension, and you'll see why hopefully. You may be confusing systems in equilibrium and accelerating systems while doing the FD.

Edit, trying to think of a good way to explain what I think is catching you up, but anyway, what's actually accelerating the system upward? The reactionary tension of course! The force that's pulling the system upward itself isn't applied to the buckets, its mediated by the tension in the rope.

Not sure if that helps or not.
 
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I think I understand! The FA isn't actually an applied force. Well it is, but in terms of this problem it isn't. It's actually just addition upward tensional force on the upper cord FT1! This would, obviously, increase FT1 and in turn increase FT2. Thanks for the help and sorry for not using the proper format of my question. Merci.
 

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MyNameIsNicholas said:
I think I understand! The FA isn't actually an applied force. Well it is, but in terms of this problem it isn't. It's actually just addition upward tensional force on the upper cord FT1! This would, obviously, increase FT1 and in turn increase FT2. Thanks for the help and sorry for not using the proper format of my question. Merci.

Edit: Ignore those files. I was going to ask a follow-up question but upon creating those images and thinking about the question, it clicked!
 
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