Question

lets say I calculate a y force to be -30 N. If I was to continue analysis, would I still assume -30N force. Or do I change the force representation to +30, and pointing upwards?

Answer 1

Are there any more forces acting in the y direction? Are you saying that the N force is acting in the same direction as gravity? The normal force should be pulling up---more details please.

Answer 2

hey @erbium1843, there are many forces, I have solved an equilibrium equation, and found out that the unknown force is -30N. This means the direction is opposite to that which I assume correct?

If so, do I now change the direction of the assume force to the correct orientation, and continue calculations. or do I leave it as -30N. thanks

Answer 3

The forces/vectors are arbitrary....it seems that you have designated the forces to be equal and opposite of each other e.g. the N and g, so if that being the case then go ahead assuming they are oriented 180 degrees from each other.

Answer 4

I meant the direction of the forces and vectors are arbitrary

Answer 5

I think you've got a mistake.

Answer 6

I am assuming he has put the vectors into the simplest component---what is my mistake?

Answer 7

No, I meant @dgamma3. The question is incoherent...