HARD

Earn 100

Ernest Rutherford devised an experiment in which alpha particles were directed at a thin gold foil. The results of this experiment showed that every atom has a nucleus, and the plum pudding model of the atom had to be discarded.

Draw a diagram to show how an alpha particle could be scattered backward by a gold atom, towards the source from which it came. Explain why most alpha particles passed straight through the gold foil.

Important Questions on Atoms

EASY

Physics>Modern Physics>Atoms>Alpha-particle Scattering and Rutherford's Nuclear Model of Atom

In Rutherford scattering experiment, what will be the correct angle of scattering for an impact parameter

b = 0

EASY

Physics>Modern Physics>Atoms>Alpha-particle Scattering and Rutherford's Nuclear Model of Atom

Particle used in the Rutherford's scattering experiment to deduce the structure of atoms

EASY

Physics>Modern Physics>Atoms>Alpha-particle Scattering and Rutherford's Nuclear Model of Atom

Define impact parameter.

EASY

Physics>Modern Physics>Atoms>Alpha-particle Scattering and Rutherford's Nuclear Model of Atom

An $\alpha$ particle with energy

7.7 MeV

approaches a stationary nucleus of

Au (Z = 79)

. Assuming both of them to be point particles, the closest it will be able to come to the

Au

nucleus is

HARD

Physics>Modern Physics>Atoms>Alpha-particle Scattering and Rutherford's Nuclear Model of Atom

A proton of mass

m

and charge

e

is projected from a very large distance towards an

α

-particle with velocity

v .

Initially

α

-particle is at rest, but it is free to move. If gravity is neglected, then the minimum separation along the straight line of their motion will be

MEDIUM

Physics>Modern Physics>Atoms>Alpha-particle Scattering and Rutherford's Nuclear Model of Atom

A particle of mass

M

and charge

q

, initially at rest, is accelerated by a uniform electric field

E

through a distance

D

and is then allowed to approach a fixed static charge

Q

of the same sign. The distance of the closest approach of the charge

q

will be

EASY

Physics>Modern Physics>Atoms>Alpha-particle Scattering and Rutherford's Nuclear Model of Atom

What conclusion is drawn from Rutherford $'$ s scattering experiment of $α ‐$ particles?

EASY

Physics>Modern Physics>Atoms>Alpha-particle Scattering and Rutherford's Nuclear Model of Atom

The graph which depicts the results of Rutherford gold foil experiment with

α

-particles is:

θ :

Scattering angle

Y :

Number of scattered

α

-particles detected
(Plots are schematic and not to scale)

EASY

Physics>Modern Physics>Atoms>Alpha-particle Scattering and Rutherford's Nuclear Model of Atom

An alpha particle accelerated through

V

volts is fired towards a nucleus. It distance of closest approach is

r .

If a proton accelerated through the same potential is fired towards the same nucleus, its distance of closest approach will be

MEDIUM

Physics>Modern Physics>Atoms>Alpha-particle Scattering and Rutherford's Nuclear Model of Atom

In the Rutherford scattering, the number of scattered alpha particles per unit area striking a fluorescent screen at a given distance from a thin foil at an angle

θ

varies with kinetic energy

E

of the alpha particle as

MEDIUM

Physics>Modern Physics>Atoms>Alpha-particle Scattering and Rutherford's Nuclear Model of Atom

In Rutherford's experiment, a thin gold foil was bombarded by alpha particles. If Thomson's "Plum Pudding Model" of the atom were correct, what would have been the outcome of the experiment?

MEDIUM

Physics>Modern Physics>Atoms>Alpha-particle Scattering and Rutherford's Nuclear Model of Atom

A beam of electrons of energy E scatters from a target having atomic spacing of

1 Å

. The first maximum intensity occurs at

θ = 60 ° .

Then

E (in eV)

is........
(Planck's constant

h = 6.64 \times 10^{- 34} J s, 1 eV = 1.6 \times 10^{- 19} J,

electron mass

m = 9.1 \times 10^{- 31} kg

)

EASY

Physics>Modern Physics>Atoms>Alpha-particle Scattering and Rutherford's Nuclear Model of Atom

Which of the following are deflected by the electric field?

MEDIUM

Physics>Modern Physics>Atoms>Alpha-particle Scattering and Rutherford's Nuclear Model of Atom

Discuss an experimental setup off Geiger -Marsden experiment of

α

- scattering.

MEDIUM

Physics>Modern Physics>Atoms>Alpha-particle Scattering and Rutherford's Nuclear Model of Atom

\sqrt{d_{1}}

and

\sqrt{d_{2}}

are the impact parameters corresponding to scattering angles

60 °

and

90 °

respectively, when an

α

particle is approaching a gold nucleus. For

d_{1} = x d_{2}

, the value of

x

will be _____ .

HARD

Physics>Modern Physics>Atoms>Alpha-particle Scattering and Rutherford's Nuclear Model of Atom

Describe Rutherford atom model. What are the draw backs of this model?

EASY

Physics>Modern Physics>Atoms>Alpha-particle Scattering and Rutherford's Nuclear Model of Atom

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 adjoing diagram. The number of alpha particles in