An `alpha`-particle of `5MeV` energy strikes with a nucleus of uranium at stationary at an scattering angle of `108^(@)`. The nearest distance up to which `alpha`particle reaches the nuvles will be of the order of

Options

A. 1 Å
B. `10^(-10) cm`
C. `10^(-12)` cm
D. `10^(-15)` cm

Answer

C

Explanation

`K=(1)/(4 pi epsilon_(0)) (Z_(1)Z_(2)e^(2))/(r_(0))`
`r_(0)=(1)/(4pi epsilon_(0)).(Z_(1)Z_(2)e^(2))/(K)`
`=(9xx10^(9)xx92exx2e)/(5xx1.6xx10^(-13))`
`=(2xx9xx92xx10^(9)xx(1.6xx10^(-19))^(2))/(5xx1.6xx10^(-13))`
` =530xx10^(-16)m=5.3xx10^(-14)m`
`=5.3xx10^(-12)`