举一反三
- The curl equation [img=154x44]1803a2a153c85f5.png[/img]shows that : A: The time-varying magnetic field can generate an electric field, in which the elecric field lines is closed around the magnetic field line. B: The time-varying magnetic field can generate a magneitc field, in which the magnetic field lines is closed around the electric field line. C: The magnetic field lines is closed themselves. D: Flux continuity
- In the vector field, the vector line is such a curve where ( ) A: The tangent direction at each point on it is orthogonal to the direction of the vector field at that point. B: The tangent direction at each point on it is parallel to the direction of the vector field at that point. C: The value of each point on it is equal to the value of the vector field at that point. D: The vector line is the geometric curve of the vector field function.
- 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
- There is no magnetic field in an ideal conductor, but there is a magnetic field inside because of the surface current。
- If F is a vector field, then divF is a vector field.
内容
- 0
There is no magnetic field in an ideal conductor, but there is a magnetic field inside because of the surface current。 A: 正确 B: 错误
- 1
一个磁场的磁感线如图所示，将一个小磁针放入磁场中，则小磁针将( )The magnetic flux line of a magnetic field is as shown in the figure. If a small magnetic needle is put into the magnetic field, the small magnetic needle will ( )[img=162x83]18035646b23e320.png[/img] A: 向右移动 Move to the right B: 向左移动 Move to the left C: 顺时针转动Turn clockwise D: 逆时针转动turn anticlockwise
- 2
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
- 3
Which of the following explains why a magnetic field does no work on a moving charged particle?( ) A: The magnetic force depends on the speed of the particle. B: There is always an electric field that cancels the work done by the magnetic field. C: The magnetic force is always perpendicular to the direction of motion. D: The magnetic force depends on the direction of motion of the particle. E: The magnetic force is conservative.
- 4
A square current loop with length a on each side carries a current I. The loop is in a uniform magnetic field B. If the loop is in the stable equilibrium, the magnetic flux passing through the loop onlyby the uniform field is ( ). A: [img=30x22]1803a3748913c57.png[/img] B: 0 C: [img=44x24]1803a37490df0b1.png[/img] D: indeterminable