AP E&M - Gauss's Law Concept Quiz

The electric flux Φ through a surface

• is the amount of electric field piercing the surface
• is the electric field multiplied by the area.
• does not depend on the area involved
• is the line integral of the electric field around the edge of the surface

What is the S.I unit of Electric Flux?

• $\frac{Nm^2}{C}$

• $Nm^2$

• $\frac{NC}{m^2}$

• $\frac{N^2C^2}{m^2}$

The area vector for a flat surface

• is parallel to the surface and has a magnitude equal to the length of a side of the surface.
• is perpendicular to the surface and has a magnitude equal to the length of a side of the surface.
• is parallel to the surface and has a magnitude equal to the area of the surface.
• is perpendicular to the surface and has a magnitude equal to the area of the surface.

A closed surface is exposed to a region of space that has no electric field. If the electric flux through the closed surface is zero, which of the following must be true.

• there must be a net charge enclosed by the surface

• the electric field must be uniform

• The closed surface must be spherically symmetrical

• None of the above

A charge Q is enclosed by a Gaussian spherical surface of radius R. If the radius is doubled, then the electric___________ will remain same.

• Electric Field

• Electric Charge

• Flux

• None of above

Four charges + 8Q, - 3Q +5Q and -10Q are kept inside a closed surface. What will be the outgoing flux through the surface.

• 26 N×m²/C

• 0 N×m²/C

• 10 N×m²/C

• 8 N×m²/C

A point particle with charge q is placed inside a cube but not at its center.  The electric flux through any one side of the cube:

• is zero
• is q/e₀
• is q/4e₀
• is q/6e₀

When a piece of paper is held with one face perpendicular to a uniform electric field the flux through it is 25 N×m²/C. When the paper is turned 25° with respect to the field the flux through it is: 

• 0 N×m²/C
• 11 N×m²/C
• 12 N×m²/C
• 23 N×m²/C

Tags

NGSS.HS-PS2-4

Charge Q is distributed uniformly throughout a spherical insulating shell. The net electric flux through the inner surface of the shell is: 

• 0
• Q/e₀
• 2Q/e₀
• Q/4*Pi*e₀

A cylindrical wastepaper basket with a 0.15-m radius opening is in a uniform electric field of 300 N/C, perpendicular to the opening. The total flux through the sides and bottom is: 

• 0 N×m²/C
• 4.2 N×m²/C
• 21 N×m²/C
• 280 N×m²/C

Tags

NGSS.HS-PS3-5