Question

An electron at rest is accelerated through the potential difference applied across anode and cathode of 200V. If the velocity of the electron is $8.4\times {10}^{6}m/s$. Then its specific charge is

• A. $1.764\times {10}^{11}C/k{g}^{-1}$
• B. $1.7\times {10}^{11}C/k{g}^{-1}$
• C. $1.42\times {10}^{11}C/k{g}^{-1}$
• D. $1.57\times {10}^{11}C/k{g}^{-1}$

Answer 1

The correct option is A $1.764\times {10}^{11}C/k{g}^{-1}$

the velocity should be of order 6. then the answer will be A