PH4129 - Q2

A neutral, hollow, metallic sphere is placed in presence of an electric field as shown. Which of the following charge diagrams represents the effect of the electric field on the conductor?

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Answer explanation

Since charges are free to move in a conductor, the external electric field will cause the sphere to be polarized. Charges reside on a surface of the conductor, thus all charge will be displaced by the electric field to settle on the shell's outer surface.

Tags

NGSS.HS-PS2-4

NGSS.HS-PS3-5

The amount of work per unit charge performed by an electric field is called _______.

Answer explanation

Which of the following properties is true of a conductor placed in an external electric field?

• The conductor acquires a charge from the external electric field.

• The conductor's internal charge moves to its center.

• The electric field inside the conductor vanishes.

• The electric field becomes parallel to the surface of the conductor.

• The external electric field strength decreases to half its value inside the conductor.

Answer explanation

A conductor is unable to sustain an internal electric field. Thus, the electric field inside a conductor is always zero (regardless of whether or not it is charged).

An electron is released from the negative plate of a parallel plate capacitor, as shown in the figure. As the electron approaches the positive plate, what is the correct change in energy it experiences?

• The electron's electric potential energy increases.

• The electron's kinetic energy decreases.

• The electron's electric potential energy decreases.

• The electron's kinetic energy remains unchanged.

• The electron's electric potential energy remains unchanged.

Answer explanation

Tags

NGSS.HS-PS3-1

Which of the following is a true property of the electric field within the plates of a charged parallel plate capacitor?

• The electric field is zero at the midpoint between the plates.

• The electric field always points from the negative to the positive plate.

• The electric field strength increases when the area of the plates is increased.

• The electric field between the plates is not conservative.

• The electric field between the plates is uniform.

Tags

NGSS.HS-PS2-4

NGSS.HS-PS3-5