A plastic sphere of mass 3.00x10^-15 kg is suspended between two horizontally oriented, charged plates. If the electric field between the plates is 6.25x10^4 N/C downwards, what is the charge on the sphere?
Hey guys! I'm struggling on my Physics and would appreciate any help. Thanks so much for your time! :)
Hey guys! I'm struggling on my Physics and would appreciate any help. Thanks so much for your time! :)
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The question is not very clear, so I could be wrong about this, but I assume that the sphere is initially charged and the sphere is floating between the two plates because the electric force on the sphere cancels (exactly) the gravitational force. So, assuming I interpreted the question correctly, here's what you have to do:
Gravitational force on sphere is:
F = mg = (3.00*10^-15) * 9.8 = 2.94 * 10^-14 N
Electric force on sphere is:
F = q*E
So if we want to solve for the charge q, we get
q = F/E = 2.94 * 10^-14 N / (6.25x10^4 N/C)
= 4.704 * 10^-19 C
Gravitational force on sphere is:
F = mg = (3.00*10^-15) * 9.8 = 2.94 * 10^-14 N
Electric force on sphere is:
F = q*E
So if we want to solve for the charge q, we get
q = F/E = 2.94 * 10^-14 N / (6.25x10^4 N/C)
= 4.704 * 10^-19 C