Gauss' Law

Question 1

Which of the following closed surfaces will have the greatest net electric flux coming out of it?
A sphere of radius R with a point charge Q at its centre.
A sphere of radius R that is concentric with a uniformly charged sphere of radius r < R carrying chargeQ
A sphere of radius 2R with a point charge Q2 at its centre.
A sphere of radius R2 with a point charge 2Q at its centre.

Answer 1

A sphere of radius R2 with a point charge 2Q at its centre.

Question 2

A sphere of radius r has a net charge +Q.  A spherical metallic shell with no net charge on it and of inner radius R1> r and outer radius R2 is concentric with the small sphere.
The outer surface of the metallic shell 
is neutral 
is negatively charged 
is positively charged

Answer 2

positively charged

Question 3

An amount of charge q is placed on a solid conducting sphere of radius r. What is the magnitude of the electric field at the centre of the sphere?
Greater than zero
Zero
None of the above

Answer 3

Zero

Question 4

What statement is not true of conductors in electrostatic equilibrium?
The electric field inside a conductor is zero
The electric field is parallel to the surface of a conductor everywhere on that surface
Any excess charge placed on a conductor resides entirely on the surface of the conductor
All of these statements are true

Answer 4

The electric field is parallel to the surface of a conductor everywhere on that surface

Question 5

5. An electric dipole is enclosed by a Gaussian sphere. Under what conditions will the electric flux be zero?When the Gaussian sphere is centred on the dipole When the Gaussian sphere is not centred on the dipole When the Gaussian sphere is very large
   When the Gaussian sphere is very small (but still encloses the dipole)
   All of the above

Answer 5

All of the above

Question 6

If a  charge qi s  placed  in  the  corner  of  a  cube,  how  many  of  the  six  cube  faces  have  anon-zero  flux?
All 
Six
Two
Three
All are zero

Answer 6

Three

Question 7

An electric dipole is placed at the origin of a coordinate system. A spherical surface of radius R is such that it encloses the dipole completely. Which statement is true?
There is a net electric flux into the surface
The electric field magnitude is constant along the surface.
The net charge enclosed by the surface is zero.
There is a net electric flux out of the surface

Answer 7

The net charge enclosed by the surface is zero