# Vector Common Point Angles

When two vectors A and B are drawn from a common point, the angle between them is (phi) .

If A and B have the same magnitude, for which value of (phi) will their vector sum have the same magnitude as A or B?

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Three horizontal ropes pull on a large stone stuck in the ground, producing the vector forces A, B, and C shown in the figure that I have attached.

(a) Find the magnitude of a fourth force on the stone that will make the vector sum of the four forces zero. I dont know how to set up this problem.

(b) Find the direction of a fourth force on the stone that will make the vector sum of the four forces zero.(counterclockwise from positive x-axis.

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In two dimensions the general vector can be written as

(1.1)

Where R is the magnitude of the vector and is the angle the vector makes with ...

#### Solution Summary

The expert examines vector common point angles.