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Two small spheres, X and Y, carrying charges of +6 x 10-6 C and +8 x 10-6 C respectively, are placed 0,20 m apart in air.
7.1 State Coulomb’s law in words. (2)
7.2 Calculate the magnitude of the electrostatic force experienced by charged sphere X. (4)
A third sphere, Z, of unknown negative charge, is now placed at a distance of 0,30 m below sphere Y, in such a way that the line joining the charged spheres X and Y is perpendicular to the line joining the charged spheres Y and Z, as shown in the diagram below.
7.3 Draw a vector diagram showing the directions of the electrostatic forces and the net force experienced by charged sphere Y due to the presence of charged spheres X and Z respectively. (3)
7.4 The magnitude of the net electrostatic force experienced by charged sphere Y is 15,20 N. Calculate the charge on sphere Z. (4)
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