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A charge Q is enclosed by a Gaussian sph...

A charge `Q` is enclosed by a Gaussian spherical surface of radius `R`. If the radius is doubled, then the outward electric flux will

A

be reduced to half

B

remain the same

C

be doubled

D

increase four times

Text Solution

AI Generated Solution

The correct Answer is:
To solve the problem, we will apply Gauss's Law, which states that the electric flux (\( \Phi_E \)) through a closed surface is proportional to the charge (\( Q \)) enclosed by that surface. The formula for electric flux is given by: \[ \Phi_E = \frac{Q}{\epsilon_0} \] where \( \epsilon_0 \) is the permittivity of free space. ### Step-by-Step Solution: 1. **Identify the Charge and Gaussian Surface**: - We have a charge \( Q \) enclosed by a Gaussian spherical surface of radius \( R \). 2. **Apply Gauss's Law**: - According to Gauss's Law, the electric flux through the Gaussian surface is given by: \[ \Phi_E = \frac{Q}{\epsilon_0} \] - This equation shows that the electric flux depends only on the charge \( Q \) enclosed within the surface and not on the radius of the surface. 3. **Change the Radius of the Gaussian Surface**: - Now, we double the radius of the Gaussian surface, making it \( 2R \). 4. **Reapply Gauss's Law**: - Even with the new radius \( 2R \), the charge \( Q \) remains enclosed within the surface. Therefore, the electric flux through the new Gaussian surface is still: \[ \Phi_E = \frac{Q}{\epsilon_0} \] 5. **Conclusion**: - Since the electric flux does not depend on the radius of the Gaussian surface, the outward electric flux remains the same when the radius is doubled. ### Final Answer: The outward electric flux will remain the same.

To solve the problem, we will apply Gauss's Law, which states that the electric flux (\( \Phi_E \)) through a closed surface is proportional to the charge (\( Q \)) enclosed by that surface. The formula for electric flux is given by: \[ \Phi_E = \frac{Q}{\epsilon_0} \] where \( \epsilon_0 \) is the permittivity of free space. ...
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Knowledge Check

  • Answer questions on the basis of your understanding of the following paragraph and the related studied concept. Electric flux, in general , through any surface is defined as per relation: phi_E= int oversetto E. oversetto (ds) , where integration has to be performed over the entire surface through which flux is required. The surface under consideration may be a closed one or an open surface. When flux through a closed surface is required we use a small circular sign on the integration symbol. Thus flux over a closed surface oint E= oint oversetto E. oversetto (ds) . it is customary to take the outward normal as positive in this case. A German physicist Gauss established a fundamental law to find electric flux over a closed surface. As per Gauss' law , the flux of the net electric field through a closed surface equals the net charge enclosed by the surface divided by in_0 . Mathematically oint oversetto (E) . oversetto (ds) =(1)/( in_0) [q_(en) ] , where q_(cn) is the net charge enclosed within the surface. It is possible to derive Gauss' law from Coulomb's laws. Gauss' law can be applied to obtain electric field at a point due to continuous charge distribution for a number of symmetric charge configurations. A charge q is enclosed by a Gaussian spherical surface of raidus R. If the radius is doubled then the electric flux will.

    A
    be doubled
    B
    increases four times
    C
    be reduced to half.
    D
    remain the same.
  • Consider a Gaussian spherical surface covering a dipole of charge q and -q, then

    A
    `q_(in) = 0` (net charge enclosed by the spherical surface)
    B
    `phi_(net) = 0` (net flux coming out the spherical surface)
    C
    `E = 0 ` at all points on the spherical surface.
    D
    `int vecE * d vecs` = 0 (surface integral of over the spherical surface)
  • A charge q is enclosed by an imaginary Gaussian surface. If radius of surface is increasing at a rate (dr)/(dt)= K , then

    A
    flux linked with surface is increasing at a rate `(dphi)/(dt)=K`
    B
    flux linked with surface is decreasing at a rate `(dphi)/(dt)=-K`
    C
    flux linked with surface is decreasing at a rate `(dphi)/(dt)=(1)/(K)`
    D
    flux linked with surface is `(q)/(epsilon_(0))`
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