A beam of fast moving alpha particles were directed towards a thin film of gold. The parts \(A, B\) and \(C\) of the transmitted and reflected beams corresponding to the incident parts \(A, B\) and \(C\) of the beam are shown in the adjoining diagram. The number of alpha particles in

According to Rutherford's \(\alpha\)-particles scattering experiment, following observations are made
(i) Most of the \(\alpha\)-particles passed through the gold foil undeflected.
(ii) Only about \(0.14 \%\) of the incident \(\alpha\)-particles scattered by an angle greater than \(1^{\circ}\).
(iii) About one \(\alpha\)-particle in every \(8000 \alpha\)-particles deflects by angle more than \(90^{\circ}\).
So, from above observation, we can conclude about the number of \(\alpha\)-particle in given figure as,
\(n_{A^{\prime}}>n_{C^{\prime}}>n_{B^{\prime}}\)
i.e., number of \(\alpha\)-particle will be maximum in \(A^{\prime}\) and minimum in \(B^{\prime}\).