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When glass rod is rubbed against silk, s...

When glass rod is rubbed against silk, silk becomes negatively charged of 320 nC, then how much electrons lost by the glass rod ?

A

(A) `2 xx 10^(10)`

B

(B) `2 xx 10^(11)`

C

(C) `2 xx 10^(12)`

D

(D) `5.12 xx 10^(-26)`

Text Solution

Verified by Experts

The correct Answer is:
C
`Q = -320 nC = -320 xx 10^(-9) C`
`e = -1.6 xx 10^(-19)` C
Q = ne
`-320 xx 10^(-9) = n xx (-1.6 xx 10^(-19))`
`therefore n = (320 xx 10^(-9))/(1.6 xx 10^(-19)) = 2 xx 10^(12)`
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KUMAR PRAKASHAN-ELECTRIC CHARGES AND FIELDS -SECTION D (MULTIPLE CHOICE QUESTIONS (MCQS)) (MCQS FROM .DARPAN. BASED ON TEXTBOOK) (ELECTROSTATIC ELECTRIC CHARGE AND FRICTIONAL ELECTRICAL CHARGE)
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