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Physics · 2026 · 2 marks
AtomsAlpha-particle Scattering and Rutherford’s Nuclear Model of Atom2 marksUnderstandvery short answer
CBSE 2026 · Region 4 · Set 1 · Q20
Draw the graph showing the variation of number of scattered alpha particles (N) detected with scattering angle ( θ ) in Geiger-Marsden experiment.…
Draw the graph showing the variation of number of scattered alpha particles (N) detected with scattering angle ( $\displaystyle \theta$ ) in Geiger-Marsden experiment. Infer two conclusions from the graph.
Marking-scheme solution
Graph
Conclusions from the graph
1. Many of the α-particles pass through the foil, without suffering any collisions.
2. Only a few incident α-particles scatter by more than $\displaystyle 1^{\circ}$.
3. About $\displaystyle 1$ in $\displaystyle 8000$ α-particles deflect by more than $\displaystyle 90^{\circ}$.
(Any Two)
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CBSE Class 12 Physics past-paper question from the 2026 board exam, with the answer as CBSE’s own marking scheme gives it. Where our answers come from.