Question

Define the term - Distance of closest approach. How will it be affected, for an α-particle, if kinetic energy of the particle is doubled?

Draw a graph showing the variation of number of particles scattered (N) with the scattering angle θ in Geiger-Marsden experiment. Why only a small fraction of the particles are scattered at θ > 90° ? Mention two limitations of Rutherford nuclear model of an atom.

In the Thomson's model of atom, which of the following statments are correct? (i) the mass of the atom is assumed to be uniformaly distributed over the atom (ii) the positive charge is assumed to be uniformaly distributed over the atom (iii) the electrons are uniformaly distributed in the positively charged sphere (iv) the electrons attract each other to stabilise the atom

The first model of an atom was given by