A $1\mathrm{.}8$ x $10$ kg charged oil drop accelerates upwards in a vertical electric field of strength $500$ N$/$C$.$ When its acceleration is upwards at $3\mathrm{.}5$ m$/$s$^2,$ the charge on the oil drop must be b x $10$ C$.$ The value of the coefficient $"$b$"$ is $\_\_\_\_.($Record your $2$ digit answer$)$

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To find the charge on the oil drop we can use the equation of motion ... View the full answer