Once again, the birds reoriented themselves to the northwest — ______ the magnetic field alone — regardless of smells or other cues, is enough to alter the birds’ mental map. The study is in the journal Current Biology.
举一反三
- There is no magnetic field in an ideal conductor, but there is a magnetic field inside because of the surface current。
- What is the source of static magnetic field? A: static charge B: steady current C: time-varing current D: the other three answer are all right.
- The birds sang to warn other birds off their ____. A: land B: region C: habitat D: territory
- Semiconductor<br/>with a current is placed in a magnetic field perpendicular to the<br/>current and it induced electric field in the direction. This<br/>phenomenon is known as the ______ .
- 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