It is of a plum cake and the electrons are like black currants in a sphere of a positive like a spherical christmas pudding
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Rutherford setup given in the given click.
Postulates of Rutherford nuclear model:

Positive charge is concentrated in the center of the atom, called nucleus.Electrons revolve around the nucleus in circular paths called orbits.The nucleus is much smaller in size than the atom..... Drawbacks of Rutherford’s Model:The orbital revolution of the electron is not expected to be stable.According to Rutherford’s model, the electrons, while moving in their orbits, would give up energy. This would make them slow down, gradually and move towards the nucleus. The electrons will follow a spiral path and then fall into the nucleus. Ultimately, the atom would collapse. But in reality the atom is stable
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