The magnetic fields generated by currents and calculated from Ampere's Law or the Biot-Savart Law are characterized by the magnetic field B measured in Tesla. But when the generated fields pass through magnetic materials which themselves contribute internal magnetic fields, ambiguities can arise about what part of the field comes from the external currents and what comes from the material itself. It has been common practice to define another magnetic field quantity, usually called the "magnetic field strength" designated by H. It can be defined by the relationship
Magnetic fields can be produced by moving electric charges and the intrinsic magnetic moments of elementary particles associated with a fundamental quantum property , their spin .   In special relativity , electric and magnetic fields are two interrelated aspects of a single object, called the electromagnetic tensor ; the split of this tensor into electric and magnetic fields depends on the relative velocity of the observer and charge. In quantum physics , the electromagnetic field is quantized and electromagnetic interactions result from the exchange of photons .
Sports, which are dangerous for us, shouldn't take part in our life. Some people aren't bothered by it because an extreme sport is the most important thing in their lives, while others are angry about it because they think that people are menaced by extreme and can break up with life.
I think that the extreme sports shouldn't be banned. Because they always allow us to be in good physical shape and have a good health. In addition, they allow us to feel something exciting and interesting. Therefore, I consider that it's an integral part of our life.
But more people also think that the extreme sports should be banned. Firstly, if someone doesn't have basic skills, he can injure and, moreover, can die. The most of them don't find anything attractive in it.
I don't agree with the opposing opinion because if you have a special equipment and proper training, you can't injure.
All in all, I think that the extreme sports play an important part in our life. Although, they're dangerous, they inspire us to explore something which is new, unknown and interesting. It allows us to be active and debonuire people.