Question:
The magnitude of point charge due to which the electric field 30 cm away has the magnitude ,$2
\, NC^{-1}$ will be
The magnitude of point charge due to which the electric field 30 cm away has the magnitude ,$2
\, NC^{-1}$ will be
Updated On: May 30, 2022
- $ 2 \times 10^{-11} \, C $
- $ 3 \times 10^{-11} \, C $
- $ 5 \times 10^{-11} \, C $
- $ 9 \times 10^{-11} \, C $
Hide Solution
Verified By Collegedunia
The Correct Option is A
Solution and Explanation
$E = \frac{kq}{r^{2}} $
$ q = \frac{Er^{2}}{k} = \frac{2 \times\left(0.3\right)^{2}}{9\times10^{9}} = \frac{2\times9 \times10^{-2} \times10^{-9}}{9}$
$ \therefore q = 2 \times10^{-11}\, C$
$ q = \frac{Er^{2}}{k} = \frac{2 \times\left(0.3\right)^{2}}{9\times10^{9}} = \frac{2\times9 \times10^{-2} \times10^{-9}}{9}$
$ \therefore q = 2 \times10^{-11}\, C$
Was this answer helpful?
0
0
Top Questions on Electric Field
- An electron of mass \( m \) with an initial velocity \( \vec{v} = v_0 \hat{i} (v_0>0) \) enters an electric field \( \vec{E} = -E_0 \hat{k} \). If the initial de Broglie wavelength is \( \lambda_0 \), the value after time \( t \) would be:
- JEE Main - 2025
- Physics
- Electric Field
- 1 tesla =
- AP POLYCET - 2024
- Physics
- Electric Field
- \( \sigma \) is the uniform surface charge density of a thin spherical shell of radius \( R \). The electric field at any point on the surface of the spherical shell is:
- MHT CET - 2024
- Physics
- Electric Field
- \(\sigma\) is the uniform surface charge density of a thin spherical shell of radius \(R\). The electric field at any point on the surface of the spherical shell is:
- JEE Main - 2024
- Physics
- Electric Field
- A long solenoid of length \(75\) cm carries a current of \(3.5\) A. If the number of turns of the solenoid is \(600\), the magnitude of the magnetic field inside the solenoid is
- TS EAMCET - 2024
- Physics
- Electric Field
View More Questions
Questions Asked in KCET exam
- Three polaroid sheets are co-axially placed as indicated in the diagram. Pass axes of the polaroids 2 and 3 make 30° and 90° with pass axes of polaroid sheet 1. If \( I_1 \) is the intensity of the incident unpolarised light entering sheet 1, the intensity of the emergent light through sheet 3 is
- KCET - 2024
- Polarization
- 8.8 g of monohydric alcohol reacts with ethyl magnesium iodide, releasing 2240 $cm^3$ of ethane at STP. This monohydric alcohol forms a carbonyl compound that answers Tollen’s test. The alcohol is:
- KCET - 2024
- Alcohols, Phenols and Ethers
- Let $\vec{a}$ and $\vec{b}$ be two unit vectors and $\theta$ is the angle between them. Then $\vec{a} + \vec{b}$ is a unit vector if:
- KCET - 2024
- Vectors
- The vectors $\overrightarrow{AB} = 3\hat{i} + 4\hat{k}$ and $\overrightarrow{AC} = 5\hat{i} - 2\hat{j} + 4\hat{k}$ are the sides of a $\triangle ABC$. The length of the median through $A$ is:
- KCET - 2024
- Vectors
- The solution of $e^{\frac{dy}{dx}} = x + 1, \, y(0) = 3$ is:
- KCET - 2024
- Integration
View More Questions
Concepts Used:
Electric Field
Electric Field is the electric force experienced by a unit charge.
The electric force is calculated using the coulomb's law, whose formula is:
\(F=k\dfrac{|q_{1}q_{2}|}{r^{2}}\)
While substituting q2 as 1, electric field becomes:
\(E=k\dfrac{|q_{1}|}{r^{2}}\)
SI unit of Electric Field is V/m (Volt per meter).