# Working out the Horizontal and Vertical Components

#### ViralRiver

That's a quick sketch. Although now that I think about it, they are vectors so I have obviously added them wrong. Regardless, two of the angles have to be 30 degrees and that alone tells me that not all sides have a length of 10CM / 20N.

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#### TwoTruths

From your description earlier, it looks like you're trying to this: draw the force line, then draw the tension lines from it to form a triangle. Is that right? If so, you will not get a correct answer out of this.

Something you could do with this triangle method is to draw both 10N lines continuously, next to a 20N line. This shows that the two y components equal the gravity force. Now draw two lines (representing the tensions) from the ends of the 10N+10N line to form a triangle. Draw a dotted line from the midpoint of the 10N+10N line to where these two new lines meet. See the method here? Here's an attempt at a sketch..

| |3
| |
| |-----------2
| |
| |1

The first line is gravity. The second is the 10+10 line. Imagine a line from 1-2 and 2-3 (those are the tensions). Measure these lines and the angles. You should see what? Notice that the triangle we formed is basically both tension triangles smushed together to form a big one that we can compare with the 20N of the force of gravity.

#### ViralRiver

I didn't understand that completely. Don't worry as I'll re-read it tomorrow morning when I'm fully concious and see what I can do :P .

#### BexJ

I don't know how I managed it but after tweaking the trianlge a bit to make it more accurate I managed to get 20N for each side but this resulted in the interior angles being..well a little bit messed up frankly. Does it matter that they add up to 120°?? At least this way the maths version stays right.

I started by drawing the 20N downwards first (The one given in the first diagram), then measured 30° from each end of the line and finally drew two long lines from each point. If you measure each line from the point at which they join to the original 20N line they should both measure 20N. I hope you get that =/ I can't say that I know it's right though but it sticks to the maths version.

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#### ViralRiver

Hmm, I just realised. I haven't added in the horizontal components, it should be an irregular pentagon.

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