Are T and T2 the Same in Physics Equilibrium Problems?

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Homework Statement


In the figures:[/B]
Diagram of a 25kg block connected by a rope labeled T to a 10kg block, which a stick figure pulls to the right with a force of 200Newtons on a horizontal frictionless surface.

Diagram of three blocks in a row on a frictionless surface: a 5kg block, a 20kg block, and a 10kg block, with tensions T1 and T2 in the connecting strings and a 200 Newtons force pulling the right block to the right.

Are T and T2 same?

Homework Equations


This is just a yes and no answer[/B]

The Attempt at a Solution


I don't want anything solved. I've actually solved it already and have gotten T2= T
NOTE( T≠T1 here)
 
Attachments
  • Diagram of three blocks in a row on a frictionless surface: a 5kg block, a 20kg block, and a 10kg block, with tensions T1 and T2 in the connecting strings and a 200 Newtons force pulling the right block to the right.
    upload_2018-6-29_13-5-14.png
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  • Diagram of a 25kg block connected by a rope labeled T to a 10kg block, which a stick figure pulls to the right with a force of 200Newtons on a horizontal frictionless surface.
    uOhajQ.png
    1.9 KB · Views: 727

Discussion

I have solved it but I'm frequently paranoid regarding the errors I make while solving questions. So wanted to make sure.
That's why I needed your help.
 
I've just suggested this method over on your other thread.

You can erase the 10kg mass and the 200n force and apply f=ma to what's left.
 
CWatters said:
I've just suggested this method over on your other thread.

You can erase the 10kg mass and the 200n force and apply f=ma to what's left.
Well, this is quite obviously equivalent. The main point is that if you have a set of ##N## unknowns you need to draw the free-body diagrams of ##N## different systems where those unknowns (and no other unknowns) appear. In this case, you can draw the fbd of the full system (which in both cases result in the same) and then choose whether or not to draw the FBD of the latter part or the rightmost box. Since ##T_1## is internal it will not appear in any of those FBDs and you end up with two unknowns, ##T_2## and ##a## or (in the first case) ##T## and ##a##.