Assertion In Rutherford's gold foil experiment, very few -particles are deflecte

In Rutherford's gold foil experiment, most α-particles passed through undeflected, some were deflected at small angles, and very few (about 1 in 8000) were deflected back by more than 90°. This back deflection occurred because the atom contains a tiny, massive, positively charged nucleus. The reason states the nucleus is heavy, which is true; the large mass ensures that when an α-particle approaches head-on, the nucleus does not recoil significantly, allowing the Coulomb repulsion to reverse the α-particle's direction. Thus, the heavy nucleus is the direct cause of the rare backscattering, making the reason the correct explanation for the assertion.