What is the third force needed for equilibrium?

[preluderacer]

Homework Statement

If I have a force of 6N in the negative i hat direction and a force of 3N in the positive j hat direction , what third force will cause the object to be in equilibrium?

Homework Equations

The Attempt at a Solution

I got the answer to be the square root of 6^2+3^2 to make it like a triangle. But I am not sure if this is right and in what direction it should be pointed.

 

[The legend]

for the direction you can use trig .. let the angle of the force required from horizontal be x..then how can you find tan x in terms of known data?

Your magnitude of force is correct so you've got to worry only about direction;

 

[preluderacer]

The possible answers says it can be clockwise or counter clock wise I can't figure out which one. I used tan and got my degrees. But idk if the vector is pointing toward the y-axis force or away from it.

 

[The legend]

try drawing the FBD and see how the forces act.

 

[preluderacer]

Ok I did, so the object is moving to the left and up. So the force I need will be opposite of that? And it will be the degrees below the positive x-axis instead of to the right of the negative y axis, because its moving faster to the left than up?

 

[The legend]

yes ... just like 2 guys push a car from the front and other two from back!