Question

Two point charges +2q and -q are enclosed within a surface s and a charge +3q is present outside the surface.what is the electric flux through the surface s

Answer 1

SOLUTION

Given

• Charges enclosed in the surface : 2q and - q

• Charge outside the surface : 3q

To finD

Electric Flux inside the surface S

We know that,

$\boxed{\boxed{\tt \phi = \dfrac{Q_{net}}{\epsilon_o}}}$

Net electric charge would be :

Q = 2q - q

» Q_net = q

The charge 3q shouldn't be considered because it isn't enclosed by the surface and flux wouldn't be affected by this charge

Electric Flux would be :

$\underline{\boxed{\sf \phi = \dfrac{q}{ \epsilon_o}}}$

Answer 2

Answer:

$\large \boxed{\sf{\phi = \frac{q}{ \epsilon_{0}} }}$

Explanation:

It's being given that,

Two point charges +2q and -q are enclosed within a surface, s.

Also, there is a +3q charge present outside the surface.

Now, we have to find the electric flux.

Let's denote the net electric flux by the symbol $\bold{\phi}$.

We know that, net electric flux through any surface depends only on the charges enclosed by it, not on the charges outside it.

Also, the net electric flux through any surface is given by,

$\large \boxed{\red{\phi = \frac{q_{net}}{ \epsilon_{0}} }}$

Here, $q_{net}= +2q - q = +q$

Hence, the net electric flux is $\bold{\dfrac{q}{\epsilon_{0}}}$