If an electric field is given by $10 \hat{i}+3 \hat{j}+4 \hat{k}$, calculate the electric flux through a surface of area $10$ units lying in $y z$ plane ....... units
$100$
$10$
$30$
$40$
In figure a point charge $+Q_1$ is at the centre of an imaginary spherical surface and another point charge $+Q_2$ is outside it. Point $P$ is on the surface of the sphere. Let ${\Phi _s}$be the net electric flux through the sphere and ${\vec E_p}$ be the electric field at point $P$ on the sphere. Which of the following statements is $TRUE$ ?
Electric charge is uniformly distributed along a long straight wire of radius $1\, mm$. The charge per $cm$ length of the wire is $Q$ $coulomb$. Another cylindrical surface of radius $50$ $cm$ and length $1\,m$ symmetrically encloses the wire as shown in the figure. The total electric flux passing through the cylindrical surface is
Explain electric flux.
Choose the incorrect statement :
$(a)$ The electric lines of force entering into a Gaussian surface provide negative flux.
$(b)$ A charge ' $q$ ' is placed at the centre of a cube. The flux through all the faces will be the same.
$(c)$ In a uniform electric field net flux through a closed Gaussian surface containing no net charge, is zero.
$(d)$ When electric field is parallel to a Gaussian surface, it provides a finite non-zero flux.
Choose the most appropriate answer from the options given below
If the electric field intensity in a fair weather atmosphere is $100 \,V / m$, then the total charge on the earth's surface is ............ $C$ (radius of the earth is $6400\,km$ )