IF;

– child 1 pulls with F_{1} = 40 N force making an angle of 30 degrees north from east

– Child 2 pulls with F_{2} = 30 N force making an angle of 60 degrees north from west

– Child 3 pulls with F_{3} force **making an angle south from west**

What does the force F_{3}**and the angle ** have to be for the net force to be ZERO, i.e., for the toy to be in equilibrium?

### Solution

the horizontal forces are equal in either side

so

F_{3} cos60 + 30 cos 60 = 40 cos 30

F_{3} X 0.5 + 30 X 0.5 = 40 X 0.866

F_{3} X 0.5 = 34.64 &#████████; ( ██████ █ ███████ )

█_{█} ██ ███ = ████████████ &#█████████; ██████

███_{███} ██ ██████ = ██████████

█_{█} = ███████████ ██ ██████

**██ _{█} = ██████████ ██**