A point charge of +Q= 6.3 μC is placed at the center of an equilateral triangle. Two additional charges of +Q are placed at two of the triangles vertices such that the radius from each of the charges to the center is 0.19m. What is the magnitude of the net electrostatic force acting on the charge in the center of the triangle?

Why does the equilibrium position of the spring change when a mass is added to the spring? will the mass oscillate around the new equilibrium position of the spring or the previous position without a mass attached to the spring? if the equilibrium position of the spring changes by 20 cm (assuming no initial mass) when a mass is added to the spring with constant 4.9 kg/s^2, what is the mass of the object attached to the spring?