举一反三
- _______________every magnet is surrounded by a magnetic field.
- _____ magnet in a magnetic field will be subject to _____ force. A: A; a B: The; the C: A; the D: the; /
- The region around a magnet where magnetic forces act is sometimes called a electric field.
- ______every magnet is surrounded by a magnetic field. A: It is believed that B: It believes that C: It believed that D: It's believing that
- Microwave oven uses electromagnetic wave to heat food. Suppose the space inside the oven can be treated as free space. If the electric field at point P in the oven is measured to be [img=144x45]18033d924610386.png[/img], then the magnetic field at point P at the same moment is B=_________T.
内容
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【单选题】What is a key characteristic of a permanent magnet alternator? A. Permanent magnet stator B. Permanent magnet rotor C. Permanent magnet rotor and stator D. The use of a strong NIB magnet
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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
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Which magnetic compass corrector（s）CANNOT be set on a heading of magnetic east or magnetic west（）. A: Heeling magnet B: Flinders bar C: Fore-and-aft magnets D: All of the above can be set on magnetic east or magnetic west heading
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The( )bulletin board has become the children’s favorite, on which they often display their creative drawings. A: magnet B: magnetic C: magnetically D: magnetize
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An inductor stores energy in a magnetic field _________ an electric field.