An electron in a certain Bohr orbit has velocity 1/275 of the velocity of light. In which orbit the electron is revolving?

An electron in a certain Bohr orbit has velocity 1/275 of the velocity

1.	An electron in a certain Bohr orbit has velocity 1/275 of the velocity of light. In which orbit the electron is revolving?
Answer» SOLUTION :Velocity of ELECTRON `= (1)/(275) xx 3 xx 10^(10) cm s^(-1) = 1.90 xx 10^(8) cm s^(-1)` Velocity of electron in nth orbit of H-like PARTICLES in C.G.S. UNITS is GIVEN by `u_(n) = (2pi Ze^(2))/(nh)` Putting Z = 1 for H and `e = 4.80 xx 10^(-10)" esu"` and `h = 6.626 xx 10^(-27)` erg sec, we get `u_(n) = (2 xx 3.14 xx (4.80 xx 10^(-10))^(2))/(n xx (6.626 xx 10^(-27))) = (2.18 xx 10^(8))/(n)` `:. (2.18 xx 10^(8))/(n) = 1.09 xx 10^(8)` (calculated above) `:. n = 2`