Seemingly simple mechanics questions

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The discussion revolves around a mechanics problem involving a box with weight mg and a tension t that is less than mg. Two scenarios are proposed: the box rising with decreasing speed and falling with increasing speed. The confusion arises regarding the concept of rising with decreasing speed, particularly how this can occur mathematically and conceptually. It is suggested that the box may have an initial velocity or tension that changes over time, leading to the observed behavior. The problem's lack of specificity regarding initial conditions is noted, prompting curiosity about the correct interpretation and solutions.
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1. Homework Statement
The problem basically states that there is a box with weight mg and a string that is less of magnitude with tension t as shown in this picture: https://gyazo.com/efeb48469cfb44399bea6c2dcc9e87c7
The question is what are two possibilities for this situation and the answers are : rising with a decreasing speed and falling with an increasing speed. I do not understand the rising with a decreasing speed aspect of it in conceptual and mathematical terms. How does this happen (in what scenario for example)?

Homework Equations

:
F=ma, mg etc.[/B]

The Attempt at a Solution


It's obvious that acceleration is negative from the start as mg has the greater magnitude (T-mg/m = a)
my thought was we either have an initial tension that decreases of some sort or we have an initial velocity above 0 for the box and it decreases as time goes on
 
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werproc said:
It's obvious that acceleration is negative from the start as mg has the greater magnitude (T-mg/m = a)
my thought was we either have an initial tension that decreases of some sort or we have an initial velocity above 0 for the box and it decreases as time goes on
Do not assume the system was previously at rest, with only mg and T<mg acting on it since. The object may have been given an initial speed by some some larger T, or by some other means.
 
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That problems seems somewhat unspecific

I can think of scenarios in which at least the last two answers apply and possible the first two as well

I am curious as to what the answer is and why
 
Kaura said:
That problems seems somewhat unspecific
I can think of scenarios in which at least the last two answers apply and possible the first two as well
I am curious as to what the answer is and why
Note the constraint mentioned here:
werproc said:
weight mg and a string that is less of magnitude with tension t
 
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