If an electron has an energy such that its de - Broglie wavelenghts is 5500 Å, then the energy value of that electron is `(h=6.6xx10^(-34)js,m_(c)=9.1xx10^(-31)kg)`

Options

A. `8xx10^(-20)j`
B. `8xx10^(-10)j`
C. 8j
D. `8xx10^(-25)j`

Explanation

de - Broglie wavelenght
`lambda = (h)/(sqrt(22mE))`
`E = (1)/(2m) ((h)/(lambda))^(2)`
`=(1)/(2xx9.1xx10^(-31))((6.625xx10^(-34))/(5.5xx10^(-7)))^(2)`
`=(1)/(182xx10^(-31))xx1.45xx10^(-54)`
`=8xx10^(-25)j`