A: are trajectories of a test charge
B: are vectors in the direction of the electric field
C: form closed loops
D: cross each other in the region between two point charges
E: are none of the above
举一反三
- If the charge on a parallel-plate capacitor is doubled: A: the capacitance is halved B: the capacitance is doubled C: the electric field is halved D: the electric field is doubled E: the surface charge density is not changed on either plate
- The<br/>magnetic field lines are used to visually describe the distribution<br/>of the magnetic field around the magnet. For the following<br/>statement,( <br/>) is wrong. A: Each<br/>magnetic field line is a closed loop curve B: No<br/>two magnetic field lines can cross each other C: The<br/>length of the magnetic field line reflects the strength of the<br/>magnetic field D: The<br/>tangential direction of any point on any of the magnetic lines is the<br/>direction of the magnetic field at that point
- The Biot-Savart Law is used to（ ） A: determine the magnetic field created by an electric current B: determine the electric field created by an electric current C: determine the force field created by an electric current D: determine the magnetic field created by individual point charges E: determine the electric field created by individual point charges
- The<br/>Biot-Savart Law is used to A: determine<br/>the electric field created by individual point charges B: determine<br/>the electric field created by an electric current C: determine<br/>the magnetic field created by individual point charges D: determine<br/>the magnetic field created by an electric current E: determine<br/>the force field created by an electric current
- On the ideal conductor surface, the relationship between the electric field lines and the conductor surface is A: the electric field lines is always pertendicular to the conductor surface. B: the electric field lines is always parallel to the conductor surface. C: there is no electri field lines exsited. D: unable to determine the relationship.
内容
- 0
A closed path followed by main magnetic flux is known as a ( ). A: Magnetic circuit B: Electric circuit C: Magnetic saturation circuit D: None of the above
- 1
Point A is a distance L to the left of a charge Q. Point B is adistance 3L to the left of point A. If the electric field atpoint A due to charge Q is E, what is the electric field atpoint B?[img=277x49]17da660b2a21250.png[/img] A: E/3 B: E/9 C: E D: 3E E: E/16
- 2
If the electric flux through a closed surface is 0, then there is no net charge inside the surface. A: 正确 B: 错误
- 3
Both electric field E and electric potential V can describe the characteristics of a field. If the electric potential at a certain point is zero, the electric field at that point has to be zero.
- 4
中国大学MOOC: If the electric flux through a closed surface is 0, then there is no net charge inside the surface.