# Tension Force

1. Sep 26, 2004

### BlackMamba

Hello again,

I'm stuck on a new problem. Again, I thought I had the correct equation but apparently not as my answer is not correct.

Here's the problem: A steel I-beam has a weight of 9.10 N and is being lifted at a constant velocity. What is the tension in each cable attached to its ends?

Here is what the picture looks like: http://www.webassign.net/CJ/4-50.gif

This is the equation I came up with to solve for this problem but apparently it isn't the correct one.

F = (2mg)cos70.0 degrees

But like I said, when solving for the above equation my answer is not correct.

Any help or direction given would be greatly appreciated.

2. Sep 26, 2004

### Pyrrhus

Well you know the weight of the Beam, i suppose this will be using uniform gravitational field, so it will be in its center of gravity, and you got two tension each with the same vertical and horizontal components, calculate the Tensions vertical components and equal them to the weight of the beam.

Also Remember Newton's 1st Law:

$$\sum_{i=1}^{n} \vec{F}_{i} = 0 \rightarrow \vec{V} = constant$$