To define the direction of magnetic field of a permanent magnet, find its poles. Lines of magnetic induction will leave the North Pole and to enter southern. Define the direction of magnetic field for the conductor with current by the rule of the gimlet.
It is required to you
- magnetic needle, right gimlet, DC power source.
Instruction
1. Definition of the direction of magnetic field constant you magnitanaydit northern and southern poles in a permanent magnet. As a rule, the North Pole is painted in blue color, and southern - in red. If it is impossible, take a magnetic needle with the known poles, and establish near a magnet pole. One of its ends will be attracted by it. If this end the South Pole, means on a magnet northern and vice versa, the North Pole was attracted – on a magnet southern. Further use the rule: lines of magnetic induction leave the North Pole of a magnet and enter the South Pole.
2. Direction of magnetic field of the direct conductor and a round with a tokomprisoyedinita the direct conductor to a current source. Consider that the direction from a positive pole of a source to negative is accepted to the direction of current. Take the right gimlet (corkscrew), and twist it in the direction of the movement of current. Rotation of a handle at the same time will show the direction of lines of magnetic induction which surround the conductor in the form of concentric circles. Connect a wire round to a source. Define the direction of the movement of current, using the same rule. Then install the gimlet perpendicular to the plane of a round and rotate its handle in the direction of the movement of current. Progress of the gimlet at the same time (is twisted or gets out) will show the direction of lines of induction of magnetic field in a round.
3. Definition of magnetic field of the coil and solenoidadlya the solenoid and the coil the direction of magnetic field is determined by one technique. Connect the device to a current source. Arrange the right hand so that four fingers showed the direction of electric current in rounds. Set aside a thumb so that it was perpendicular to four fingers showing the direction of electric current. It will also show the direction of magnetic field in the coil or the solenoid. It should be noted that in them power lines of magnetic field straight lines.