Question

a negative test charge experiences a force to the right as a result of an electric field. which is the best conclusion to draw based on this description?
○ the electric field points to the left because the force on a negative charge is opposite to the direction of the field.
○ the electric field points to the right because the force on a negative charge is in the same direction as the field.
○ no conclusion can be drawn because the sign of the charge creating the field is unknown.
○ no conclusion can be drawn because the amount of charge on the test charge is unknown.

Explanation:

The direction of the electric field is defined as the direction a positive test charge would experience a force. For a negative test charge, the force is opposite to the electric field direction. Since the negative test charge experiences a force to the right, the electric field must point to the left. The sign of the charge creating the field or the amount of test charge doesn't affect the relationship between the electric field direction and the force on a negative charge. So the first option is correct.

Answer:

A. The electric field points to the left because the force on a negative charge is opposite to the direction of the field.