MCQ
Two concentric conducting thin spherical shells of radii $a$ and $b\ (b > a)$ are given charges $Q$ and $ -2Q$ respectively. The electric field along a line passing through centre as a function of distance $(r)$ from centre is given by
- ✓
- B
- C
- D
✓
Answer
Correct option: A.
a
for $\mathrm{r}<\mathrm{a}, \mathrm{E}=0$
for $\mathrm{r}<\mathrm{a}, \mathrm{E}=0$
for $a < {\rm{r}} < {\rm{b}},\overrightarrow {\rm{E}} = - \frac{{{\rm{kQ}}}}{{\rm{r}}}\widehat {\rm{r}}$
for $\mathrm{r}>\mathrm{b}, \overrightarrow{\mathrm{E}}=-\frac{\mathrm{k} \mathrm{Q}}{\mathrm{r}^{2}} \hat{\mathrm{r}}$
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