Find out the number of waves made by a Bohr's electron in one complete revolution in its third orbit.

Answer

3

Explanation

The radius fo Bohr's orbit for H-atom
` r_(1H) = 0. 529 xx 10^(-8) cm`
` :. R_(3H) =0 529 xx 10^(-8) xx (3) cm`.
And velocity ` (u_1)` for H-atom
` = 2. 1847 xx 10^8 cm sec^(-1)`
` :. U_3 = u_1 /n = ( 2 . 1847 x 10^8)/3`
Now no. of waves ` = ( 2 pi r_3)/( lambda) = ( 2 pir_3)/( h//nu-3) ( :. lambda = h/( mu))`
` = ( 2 xx 3. 14 xx 0. 259 xx 10^(-8) xx 9. xx 9. 1 xx 10^(-238) xx 2 .1847 xx 10^8)/( 6.626 xx 10^(-27) xx 3)`
` =3`
Note : no. of waves made by an electron in Bohr's orbit si equal to no. of orbit .