Grade 12th passElectrostatics
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80cm |  |
30cmThe diagram shows two equal small metal spheres of 0.004kg each. The metal spheres carry equal positive charges on them. They are 30cm apart when they are in equilibrium by a repulsive force, F. The strings on which the metal spheres are attached are in-extensible and are fixed to a point C are are 80cm long.
(1). Take one of the metal spheres and draw a free-force diagram to show the forces acting on it,
(2). Show that the repulsive force, F is given F=mgtanθ,
(3). Find the value of θ and hence fine the magnitude of the repulsive force, F
(4). Calculate the tension in each string,
(5). Assuming the distances between the two spheres are measured from the centres of the spheres, calculate the magnitude of the charges on the sphere.
(TAKE g=10m/s2)
