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A beam of electrons moving at a speed of...

A beam of electrons moving at a speed of `10^(6)m//s` along a line produces a current of `1.6xx10^(-6)` A. The number of electrons in the 1 metre of the beam is

A

(a)`10^(6)`

B

(b)`10^(7)`

C

(c)`10^(13)`

D

(d)`10^(19)`

Text Solution

Verified by Experts

The correct Answer is:
B
i=`(q)/(t)`=(q)/(x//v)`=`(qv)/(x)`=("nev")/(x)` `rArr` n=`(ix)/(ev)`=`(1.6xx10^(-6))/(1.6xx10^(-19))`=`10^(2)`
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