# A charged particle of mass 0.003g is held stationary in a space by placing it in a downward direction of electric field of 6×10^4NC^{-1}. Then, the magnitude of charge is

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A charged particle of mass 0.003g is held stationary in a space by placing it in a downward direction of electric field of $$6×10^4NC^{-1}$$. Then, the magnitude of charge is:

(A) $$5×10^4 C$$

(B) $$5×10^{-10}C$$

(C) $$5×10^{-6} C$$

(D) $$5×10^{-9} C$$

The correct option of this question is (B)

Solution :

We know that,

$$qE=mg$$

$$So, q = \frac{mg}{E}$$

$$\\=\frac{3×10^-6×10}{6×10^4}$$

$$=\frac{30×10^{-10}}{6}$$

$$=5×10^{-10}C$$