# Homework Help: Tension in ropes connecting blocks

1. Mar 14, 2005

### sevens

The figure shows two 1.0 kg blocks connected by a rope. A second rope hangs beneath the lower block. Both ropes have a mass of 250 g. The entire assembly is accelerated upward at
3.0 m/s^2
i found the force that pulls the system to be 32.0N
However the followup question states:
What is the tension at the top end of rope 1?

for a I have
$$\sum{}\ = F - T = ma$$

and for b I have

$$\sum{}\ = T - W = ma$$

since i knew my a was 3.0 m/s^2 i made the equations equal to each other, to find my tention.
$$(T - W)m = (F-T)m$$

I arived at the answer 25.1N which is wrong. i think it may have to do with the fact that the ropes have a mass I thought tension through out a rope was uniform no matter where on the string you are. :grumpy:

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2. Mar 17, 2005

### xangel31x

ok you do it the same way you did the first part, except this time you only count the mass until the end of the first rope. i did this problem a couple of weeks ago. you are doing it on online homework aren't you?