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प्रश्न
With the help of a neat labelled diagram, describe the Geiger- Marsden experiment
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उत्तर
Geiger–Marsden experiment:
The setup of the Geiger–Marsden experiment is as shown below.
In this experiment, a narrow beam of α-particles from a radioactive source was incident on a gold foil. The scattered α-particles were detected by the detector fixed on a rotating stand. The detector used had a zinc sulphide screen and a microscope.
The α-particles produced scintillations on the screen which could be observed through a microscope. This entire setup is enclosed in an evacuated chamber.
They observed the number of α-particles as a function of scattering angle. Now, the scattering angle is the deviation (θ) of α-particles from its original direction.
They observed that most α-particles passed undeviated and only a few (~0.14%) scattered by more than 1°. Few were deflected slightly and only a few (1 in 8000) deflected by more than 90°. Some particles even bounced back with 180°.
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संबंधित प्रश्न
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Answer the following question, which help you understand the difference between Thomson’s model and Rutherford’s model better.
Is the average angle of deflection of α-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?
Answer the following question, which help you understand the difference between Thomson’s model and Rutherford’s model better.
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How will the distance of closest approach be affected when the kinetic energy of the α-particle is doubles?
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Useful data
`1/(4 pi ∈_0) = 8.99 xx 10^9` newton m2C-2; c = 1.60 × 10-19 C; leV = 1.60 × 10-19j.
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