1.A beam of electrons is inci
ima)vw;tjn2 ec1/h8 tdent on an iron foil (Z=56) and electrons are diffracted. In the experiment, electrons have initial kinetic energy of 42 GeV.
j;teva) 8wnh1cm/ 2ti The first diffraction minimum is observed at an angle of $49^{\circ}C$ from the average position of most of the electrons detected.
(1)Calculate the density of the iron nucleus. $ρ$ =
$\times10^{17}\,kgm^{-3}$
(2)Using the diffraction information given, estimate the radius $r$ of the iron nucleus . r =
$\times10^{-15}\,m$
2.In another experiment, alpha particles are emitted towards iron foil with an initial kinetic energy of $125\,ke\,V$. Estimate the distance of the closest approach to the iron nucleus of the alpha particles. r =
$\times10^{-14}\,m$