Question

Which is true about an electron-
(a). rest mass of electron is `9.1xx10^(-28)g`
(b). mass of electron increases with the increase in velocity
(c). molar mass of electron is `5.48xx10^(-4)g//"mole"`
(d). `e//m` of electron is `1.7xx10^(8) "coulomb"//g`
A. Rest mass of electron is `9.1xx10^(-28) g`
B. Mass of electron increases with the increase in velocity
C. Molar mass of electron is `5.48xx10^(-4) g//mole`
D. `e//m` of electron is `1.7xx10^(8) coulomb//g`

Answer 1

Correct Answer - A, B, C, D
`m_(e)=9.1xx10^(-31)kg=9.1xx10^(-28) g`
`m=m_(0)/sqrt(1-v^(2)/c^(2)) (m_(0): "rest mass , m : dynamic mass")`
`As vuarr, (1-v^(2)/c^(2))darr :. m uarr`
Molar mass of `e=9.1xx10^(-28)xx6.023xx10^(23)=5.48xx10^(-4) g//`mole