Identify the option which is correct w.r.t structure of an atom .

Options

A. As per Rutherfor model if number of particles deviated by an angle `60^(@)` is x then those deviated by `90^(@)` will be `sqrt(2)x`
B. Specific charge of a particle projected towards the nucleus of atomic number 29 having a closest distance of approach is 2.9Å is `(10^(8))/(18)` col/kg if it is projected at an initial speed of `4xx10^(4)`
C. In the Milikan's oil drop experiment of determining charge on the cathode ray particle `4.8xx10^(-19)col`. Cannot be obtained as the charge the oil drop
D. An `alpha`-particle projected closer to the centre of the atom will experiece a lesser deviation as compared to the particle projected away from the centre.

Answer

B

Explanation

`N(theta)alpha=1/(sin^(4)((theta)/2))rArr x/y=(sin^(4)45)/(sin^(4)30) =16/4=4`
`y=4x`
`(B) (K(29e)q)/(r_(0))=1/2 mv^(2)`
`q/m=1/2xx(16xx10^(8)xx2.9xx10^(-10))/(9xx10^(9)xx29xx1.6xx10^(-19)) =(10^(8))/18`
(C) `1.6xx10^(-19)xxn=4.8xx10^(-19)`
n=3