# Forces in balance

1. Feb 3, 2015

### clockworkrobot

Hi all,

I am an architect student in college and I am trying to calculate the reactions in the question in the follwing url ( https://www.flickr.com/photos/123626386@N07/16250310830/ ) I have attempted the question and got two values which can be seen in the following url (https://www.flickr.com/photos/123626386@N07/16251461949/ ) . What I don't understand though is how to calculate whether the reaction is clockwise or anticlockwise thus assigning it a positive or negative value if anyone could tell how to do this and whether my answers are correct it would be greatly appreciated!

Many thanks,
Clockworkrobot

2. Feb 3, 2015

### haruspex

The reactions are forces, not torques, so there is no question of clockwise or anticlockwise for those.
To deduce them, you wrote a torque equation. In the way you've written it, you've taken the reactions as positive upwards, but the loads as positive downwards. That required you to reverse the signs.
A purist might have written the equation so that all forces are positive upwards and all torques positive anticlockwise, giving
RL*0 + (-25)*0.4 + (-10)*0.6 + RR*1.2 = 0.