Rankers Physics

Electric Field: Practice Problem & Solution

A spherical conductor of radius $10 \text{ cm}$ has a charge of $3.2 \times 10^{-7} \text{ C}$ distributed uniformly. What is the magnitude of electric field at a point $15 \text{ cm}$ from the centre of the sphere? (2020) $(\frac{1}{4\pi \epsilon_0} = 9 \times 10^9 \text{ N m}^2/\text{C}^2)$
$1.28 \times 10^5 \text{ N/C}$
$1.28 \times 10^6 \text{ N/C}$
$1.28 \times 10^7 \text{ N/C}$
$1.28 \times 10^4 \text{ N/C}$

Solution Explained:

To solve this problem, we apply the core principles of Electric Field. Understanding the underlying formula is key to arriving at the correct answer below:

Electric field $E = \frac{kq}{r^2}$. Substituting the given values, $E = \frac{9 \times 10^9 \times 3.2 \times 10^{-7}}{(0.15)^2}$. Solving this yields $E = 1.28 \times 10^5 \text{ N/C}$.

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Similar Practice Questions

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1. Two uniformly charged co axial rings are present as shown in the figure. Find electric field intensity at the centre of the smaller ring.
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