Tension on a rope with significant mass

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The discussion focuses on calculating the acceleration of a rope with significant mass under tension. The user attempts to derive the equation for horizontal acceleration, considering both the difference in tension (T2 - T1) and the gravitational force (mg). However, they realize that the equation should not include the mass (m) and that gravity does not affect horizontal motion in this context. A clarification emphasizes that the weight of the rope acts vertically and does not contribute to horizontal acceleration. The key takeaway is to focus solely on the tension difference for the horizontal acceleration equation.
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Homework Statement



Consider a rope that, unlike those usually studied in mechanics problems, actually has a significant mass "m". The tension at the right end of this rope is T2 and that at the left end is T1. (figure1.0) The rope has an acceleration a_rope to the right.

MFS_3l_10_c.jpg


Complete the following equation for the acceleration of the section of the rope of mass m, taking the positive direction to be to the right.

F_rope = m*a_rope = ?

Give your answer in terms of T_1, T_2, and constants such as g.

The Attempt at a Solution



I'm thinking that the Force on the rope will be an addition between the tension difference that leads to the acceleration, and the force of gravity pulling it down.

So m*a_rope = (T_2 - T_1) + mg

However, since the answer can't include m, I'm kind of lost as to where to go from here. I might just be overlooking something simple, but some insight would be really helpful

Thanks!
 
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You are writing the equation for horizontal acceleration. The weight is not along the horizontal.
At least not here...
 
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