Kinematics Newton's Laws Question

AI Thread Summary
The discussion revolves around calculating the acceleration and tension in a system involving two boxes connected by a heavy rope. The user determined the acceleration of both boxes to be 1.458 m/s² using the total mass and applied force. However, there is confusion regarding the tension in the rope, as it is assumed to be constant throughout, which is incorrect due to the rope's mass. The tension at each end of the rope differs, with the end connected to the heavier box experiencing greater tension than the end connected to the lighter box. The user plans to seek further clarification from their teacher for a better understanding.
davidkis
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Suppose the cord in Fig. 4-22 is a heavy rope of mass 1.0 kg. Calculate the acceleration of each box and the tension at each end of the cord, using the free-body diagrams shown in Fig. 4-46. Assume the cord doesn't sag. (m1 = 10.5 kg , m2 = 12.5 kg and FP = 35.0 N)

m1 stands for the mass of the first box and m2 stands for the mass of the second fp is the force that the man is pulling on the rope which is connected to m1 and anther rope connecting m1 to m2 which is 1 kg.
[m2]t2---1kg rope---t1[m1]- Fp

above is a small illustration of how it looks like I am trying to solve for t1 and t2 then tensions.

Homework Equations


so their are 2 boxes one being pulled by anther by a 1 kg string i found the acceleration of both boxes to be 1.458 m/s^2 by doing f=ma mass was 24kg and force is 35 35/24 = acceleration i had no idea where to start looking for the tension of the two boxes.


The Attempt at a Solution



have to idea i think it would be 35N because the tension would stay the same through out but doesn't seem to be right. Any Ideas?
 
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Welcome to PF!

Hi davidkis ! Welcome to PF! :smile:
davidkis said:
… a heavy rope …

i think it would be 35N because the tension would stay the same through out but doesn't seem to be right. Any Ideas?

Because the rope is heavy, the "front" end has to pull more mass than the "back" end …

it's like a series of weights hanging from the ceiling, each joined to the one above by a (massless) string …

if you think about it, the lowest connecting string has to support far less weight than the highest one, and so its tension will be far less. :wink:
 
i get where your going and tried to imagine it hanging down ur right that t2 would have less tension but i still don't completely understan might go to my teacher for this one.
 
thanks for the help tho
 
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