The intensity of the electric field required to keep a water drop of radius 10^-5 cm justsuspend in air when charged with one electron is approximately.

The intensity of the electric field required to keep a water drop of r

1.	The intensity of the electric field required to keep a water drop of radius 10^-5 cm justsuspend in air when charged with one electron is approximately.
Answer» (A) 130V/cm (B) 26V/m (C) 130 N/C (D) 260 N/C Solution :F=Ee mg =Ee `THEREFORE E = (mg)/e = (4/3pi^(2)rhog)/e` `=(4 xx 3.14 xx (10^(-7))^(3) xx 10^(3)xx 9.8)/(3 xx 1.6 xx 10^(-19))` `=25.643 xx 10^(1) = 256` = 260 N/C (UPTO two SIGNIFICANT numbers)

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The intensity of the electric field required to keep a water drop of radius 10^-5 cm justsuspend in air when charged with one electron is approximately.

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