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66. A small drop of water is suspended motionless in air by a uniform electric field
that is directed upward and has a magnitude of 8480 N/C. The mass of the
water drop is 3.50 x 10-9 kg. (a) Is the excess charge on the water drop positive or negative?
Why? (b) How many excess electrons or protons reside on the drop? |
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To suspend the water in air,
the force from the electric field must point up, so that tells us the charge
must be positive since the force is in the same direction as the applied
electric field. |
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Solve for q |
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Solve for number of fundamental
charges must be present. |
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