What is the velocity of a BB pellet that is 0.02kg and has 36 J of KE

Basically, this figure represents scattering of alpha particles by the atoms of a gold foil.

Here, A represents that a few alpha particles are deflected through large angle. It shows that the nucleus of the atom is positively charged which repels the positively charged alpha particles and deflect them from their original path.B represents that most alpha particles pass straight through the gold foil without any deflection from their original path. The reason is that there is a lot of empty space in the atom.C represents that some alpha particles are deflected through small angles. The reason is same as that of A.

Hope you could understand.

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