Target Exam

CUET

Subject

Physics

Chapter

Electric Charges and Fields

Question:

If the net flux through a cube is $1.05\, N m^2\, C^{-1}$, what will be the total charge inside the cube? (Given: The permittivity of free space is $8.85 × 10^{-12}\, C^2\, N^{-1}\, m^{-2}$).

Options:

$9.29 × 10^{-11} C$

$9.27 × 10^{-10} C$

$9.22 × 10^{-6} C$

$9.29 × 10^{-12} C$

Correct Answer:

$9.29 × 10^{-12} C$

Explanation:

The correct answer is Option (4) → $9.29 × 10^{-12} C$

$\text{Given: } \, \Phi = 1.05 \, \text{N·m}^2\text{C}^{-1}, \, \varepsilon_0 = 8.85 \times 10^{-12} \, \text{C}^2\text{N}^{-1}\text{m}^{-2}$

Using Gauss's law,

$\Phi = \frac{q}{\varepsilon_0}$

$\Rightarrow q = \Phi \varepsilon_0$

$q = 1.05 \times 8.85 \times 10^{-12}$

$q = 9.29 \times 10^{-12} \, \text{C}$

$\text{Answer: } \, q = 9.29 \times 10^{-12} \, \text{C}$