When can an object remain at rest with multiple applied forces?

[Kalie]

In an inertial frame of reference, a series of experiments is conducted. In each experiment, two or three forces are applied to an object. The magnitudes of these forces are given. No other forces are acting on the object. In which cases may the object possibly remain at rest?

The forces applied are as follows:

2 N; 2 N
200 N; 200 N
200 N; 201 N
2 N; 2 N; 4 N
2 N; 2 N; 2 N
2 N; 2 N; 3 N
2 N; 2 N; 5 N
200 N; 200 N; 5 N

I figured that A and B and C were the only ones possible since the net force could add up to 0 but it says I'm wrong...
I think there is some conscept I am missing
help?

 

[neutrino]

Can they add up to 0 in case C?

 

[Kalie]

I thought so, but i tried a and b together and that was wrong too
...sorry I ment d

 

[neutrino]

There are actually 3 cases in which they can add up to 0. A and B are two, you need to find the third.

 

[Kalie]

is it d? because that is what i tried and it was wrong

 

[neutrino]

D should be right. A, B and D are the answers.

 

[Kalie]

there is more than 3 it told me

 

[neutrino]

I guess it could also work in E,F and H...the equal forces in those cases could act in certain direction for the resultant force to be equal to third force in each case.

Edit: I meant H, not G. Sorry.

 

[Kalie]

awesome it worked thank i should of thought about it acting on them from angles