A2 - Electric fields

In the diagram below, P is a point near a negatively charged sphere. Which direction best represents the direction of the electric field at point P?

• Right
• Left
• Up 
• Down

Which of the following statements is false about electric field lines

• electric field lines cannot cross
• electric field lines point away from positive charge
• electric field lines are always straight lines
• electric field lines show how a proton would move in an electric field

At which point is the electric field the strongest

• A
• B
• C
• D

An electrostatic force of 2 X 10^-2 Newtons is exerted on a charge of 4 micro coulomb at point P in an electric field. The magnitude of the electric field intensity at P is

• 5 X 10² N/C

• 5 N/C

• 50 N/C

• 5000 N/C

The electric potential at a distance of 4 m from a certain point charge is 200 V relative to infinity. What is the potential (relative to infinity) at a distance of 2 m from the same charge?

• 600 V
• 50 V
• 200 V
• 400 V

A spherical conductor is given a positive charge. Under electrostatic conditions, which of the following is TRUE of the electric field just beneath the surface of the sphere?

• The electric field is directed away from the center of the sphere.

• The electric field in infinitely large.

• The electric field is zero.

• The electric field depends on the radius of the sphere.

• The electric field is directed tangential to the surface of the sphere.

Based on the arrangement of the electric field lines in the diagram, what are the charges?

• both charges are the same

• the charges are opposite

• they are neutral; no charge

Which statement best describes the electric fields in the image?

• The charges are neutral.

• Both charges are negative, so the field lines are alike.

• The field lines move toward a positive charge and away from a negative charge.

• The field lines move away from a positive charge and toward a negative charge.

The electric field inside a spherical shell of uniform surface charge density is

• Constant, less than zero

• Directly proportional to the distance from the centre

• zero

• None of the above

Q_A and Q_B are two charges creating an electric field. Based on the electric field lines, we can conclude

• Q_A and Q_B are both positive
• Q_A and Q_B are both negative
• Q_A is positive and Q_B is negative
• Q_A is negative and Q_B is positive