Question

A cureent of 9.6 mA is flowing through a wire.Number of electrons passing through any cross-section of the wire per minute is:

• A. $1.0\times {10}^{15}$
• B. $3.6\times {10}^{18}$
• C. $6.0\times {10}^{16}$
• D. $6.0\times {10}^{19}$

Answer 1

Answer: (B)

$3.6\times {10}^{18}$

Given,

Current (charge per second) $=9.6mA=9.6\times {10}^{-3}C/s$

Charge on each electron, $e=1.6\times {10}^{-19}C$

Number of electrons passing in one second $=\frac{9.6\times {10}^{-3}}{1.6\times {10}^{-19}}=6\times {10}^{16}electrons$

Number of electrons passing in one minute $=6\times {10}^{16}\times 60=3.6\times {10}^{18}electrons$