Three forces acting at a point keep it in equilibrium . If the angle between two of the forces , 3 N and 3 Nis 120°, then the third force is

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Explanation:

The force necessary to maintain equilibrium depends on the directions of the two forces that are separated by 120°. If both are pointing toward or away from the point, the third force will be pointing that same direction. It will be 120° from the other two, and the same magnitude (3 N).

If the one of the two forces is pointing toward, and the other is pointing away, then the third force will have magnitude 3√3 N, and will be 30° from one of the other forces. This is illustrated in the 2nd attachment.

can be answered using momentum.

momentum = p

p1= mass1 * velocity1

p1 = p2

therefore

p1 = 6kg * 4m/s

p1 = 24kgm/s

p2=m2 * v2

24 kgm/s = 7kg * v2

v2 = 24 kgm/s / 7kg

v2= 3.42 m/s