(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A block with mass 'M' is attached to the lower end of a vertical, uniform rope with mass 'm' and length 'L'. A constant upward force 'F' is applied to the top of the rope, causing the rope and block to accelerate upward. Find the tension in the rope at a dstance 'x' from the top end of the rope, where 'x' can have any value from 0 to 'L'.

2. Relevant equations

Newton's Second and Third Laws.

3. The attempt at a solution

I'm a bit confused on this question. I've tried breaking the problem up into three parts - one for the block mass 'M', one for the top of the rope and one for a point 'x' on the rope - but I can't seem to get it to work. The actual constant force there is annoying too - for the top of the rope I have a force acting downwards of (m+M)g, and an upwards force that is greater than that of 'F', but I dont know how I can equate etc. The answer is F[M+m(1-x/L)]/(M+m) but I want to know why.

Thanks in advance.

**Physics Forums | Science Articles, Homework Help, Discussion**

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Tension on a rope with mass

**Physics Forums | Science Articles, Homework Help, Discussion**