Two spheres, X and Y, are 8 meters apart. The charge on sphere X is 2 microcoulombs and the charge on sphere Y is 1 microcoulomb. If F is the
magnitude of the force of X on Y, then what is the magnitude of the force of Yon X?

answer: 2×10^-2kg

explanation: density= mass per volume

vol=mass/density

converting to s.i units we have;

3÷1000kg = 0.003

1.5÷100m = 0.15

0.003/0.15 = 0.02kg

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