You charge a piece of aluminum foil$\mathrm{ (}$mass $=3\mathrm{.}09$ g$)$ by touching it to a charged rod. The charged rod gives the aluminum foil a charge of $14$C$.$ Your professor brings a charged plate over and tells you to put the aluminum foil on top of the plate. To your surprise the aluminum foil hovers motionless in the air above it$!$ Calculate the value of the electric field from the charged plate $($assume it is a uniform field and the aluminum foil is a point charge$).$

 

 

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The hovering of the aluminum foil indicates that the electrical force on t... View the full answer