An early model for an atom considered it to have a positively charged point nucleus of charge Ze, surrounded by a uniform density of negative charge up to a radius R. The atom as a whole is neutral. For this model, what is the electric field at a distance r from the nucleus? (If r

ChemistryElectrostaticsNEET

Options:

• A $\frac{Ze}{4\pi {{\epsilon }_{0}}}\left( \frac{2}{{{r}^{2}}}-\frac{r}{{{R}^{3}}} \right)$
• B $\frac{Ze}{4\pi {{\epsilon }_{0}}}\left( \frac{1}{{{r}^{2}}}-\frac{r}{{{R}^{3}}} \right)$
• C $\frac{Ze}{4\pi {{\epsilon }_{0}}}\left( \frac{R}{{{r}^{2}}}-\frac{r}{{{R}^{3}}} \right)$
• D $\frac{Ze}{4\pi {{\epsilon }_{0}}}\left( \frac{1}{{{r}^{2}}}-\frac{2r}{{{R}^{3}}} \right)$