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Answer the following questions, which you understand the difference between Thomson's model and Rutherford's model better.
(a) Is the average angle of deflection of $\alpha$-particles by a thin gold foil predicted by Thomson's model much less, about the same, or much greater than that predicted by Rutherford's model?
(b) Is the probability of backward scattering (i.e. scattering of $\alpha$-particles at angles greater than $90^{\circ}$ ) predicted by Thomson's model much less, about the same, or much greater than that predicted by Rutherford's model?
(c) Keeping other factors fixed, it is found experimentally that for small thickness $t$, the number of $\alpha$-particles scattered at moderate angles is proportional to $t$. What clue does this linear dependence on $t$ provide?
(d) In which model is it completely wrong to ignore multiple scattering for the calculation of average angle of scattering of $\alpha$-particles by a thin foil?
(a) Is the average angle of deflection of $\alpha$-particles by a thin gold foil predicted by Thomson's model much less, about the same, or much greater than that predicted by Rutherford's model?
(b) Is the probability of backward scattering (i.e. scattering of $\alpha$-particles at angles greater than $90^{\circ}$ ) predicted by Thomson's model much less, about the same, or much greater than that predicted by Rutherford's model?
(c) Keeping other factors fixed, it is found experimentally that for small thickness $t$, the number of $\alpha$-particles scattered at moderate angles is proportional to $t$. What clue does this linear dependence on $t$ provide?
(d) In which model is it completely wrong to ignore multiple scattering for the calculation of average angle of scattering of $\alpha$-particles by a thin foil?
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(a) About the same as we are talking about average angle of deflection.
(b) Much less as in Thomson's model there is no such thing as a massive central core called nucleus.
(c) This implies that scattering of $\alpha$-particles is due to single collision only. If thickness increases then chances of single collision increases because the number of target atoms would increase. Thus, moderately scattered $\alpha$ particles would increase in number.
(d) In Thomson's model, positive charge is uniformly spreadout, hence there would be hardly any noticeable deflection due to single collision. Hence, multiple scattering has to be considered for average scattering angle.
In Rutherford's model most of the scattering is due to single collision hence multiple scattering can be ignored.
(b) Much less as in Thomson's model there is no such thing as a massive central core called nucleus.
(c) This implies that scattering of $\alpha$-particles is due to single collision only. If thickness increases then chances of single collision increases because the number of target atoms would increase. Thus, moderately scattered $\alpha$ particles would increase in number.
(d) In Thomson's model, positive charge is uniformly spreadout, hence there would be hardly any noticeable deflection due to single collision. Hence, multiple scattering has to be considered for average scattering angle.
In Rutherford's model most of the scattering is due to single collision hence multiple scattering can be ignored.
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