JEE MAIN - Physics (2025 - 8th April Evening Shift - No. 16)
Electric charge is transferred to an irregular metallic disk as shown in the figure. If $\sigma_1$, $\sigma_2$, $\sigma_3$ and $\sigma_4$ are charge densities at given points then, choose the correct answer from the options given below:
_8th_April_Evening_Shift_en_16_1.png)
A. $\sigma_1>\sigma_3 ; \sigma_2=\sigma_4$
B. $\sigma_1>\sigma_2 ; \sigma_3>\sigma_4$
C. $\sigma_1>\sigma_3>\sigma_2=\sigma_4$
D. $\sigma_1<\sigma_3<\sigma_2=\sigma_4$
E. $\sigma_1=\sigma_2=\sigma_3=\sigma_4$
Explanation
Therefore, the relationship between charge density and ROC at different points can be expressed as:
$ \sigma \propto \frac{1}{\mathrm{ROC}} $
From this, the relationship between the charge densities at the specified points becomes clear:
$ (\mathrm{ROC})_1 < (\mathrm{ROC})_3 < (\mathrm{ROC})_2 = (\mathrm{ROC})_4 $
This implies:
$ \sigma_1 > \sigma_3 > \sigma_2 = \sigma_4 $
Thus, the charge density is greatest at the point with the smallest ROC and decreases as the ROC increases, keeping in mind that $\sigma_2$ and $\sigma_4$ have equal ROC, hence equal charge densities.
Comments (0)
