A* B*
C* D*
square of side 10 cm
I tried my best to do the drawing. It is supposed to be a square, but each * is a point. The sides are 10 cm long.
The problem asks for you to find the magnitude and the direction of the net gravitational force on mass A due to the other masses.
Two of the forces from the nearest corners are perpendicular and add as vectors to form a resultant that is a single force along a diagonal. The attractive force due to the other particle at the far corner is also along the same diagonal, towards point C.
Use Newton's law of gravity to add the three forces as vectors.
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