Page 2 - 3. LESSON NOTES-(RUTHERFORD'S ALPHA PARTICLE SCATTERING EXPERIMENT & DISCOVERY OF NUCLEUS)
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Rutherford’s Nuclear model or Planetary model of an Atom:

               Rutherford gave the Nuclear model or Planetary of an atom based on his experiment
               which suggests that -

                 Atoms contain a lot of unoccupied space

                 There is a heavily positively charged substance present in the centre of the atom
                  which is called the nucleus

                 The nucleus contains an equal amount of positive and negative charge.

               The Nucleus of an Atom
                 The nucleus is located at the centre of the atom.

                 All the mass of the atom is because of the nucleus.

                 The electrons revolve around the nucleus in circular parts which are called Orbits
                  like the planets around the sun.
                 If we compare the size of the atom and nucleus, the nucleus is much smaller than
                                                         the atom.

               Drawbacks of the Rutherford’s Nuclear Model or Planetary model of an
               Atom


                     He explained that the electrons in an atom revolve around the nucleus in well-
                       defined orbits. Particles in a circular orbit would experience acceleration.
                     According to Maxwell any charged particle in accelerated motion will lose
                       energy in the form of radiations, thus the revolving electron would lose energy
                       and finally fall into the nucleus.
                     But this cannot take place as the atom would be unstable and matter would
                       not exist in the form we know.






























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