MAGNETIC FIELD OF AN OBLIQUE WINDING SOLENOID

The magnetic field of an oblique winding solenoid is explored by using the Biot-Savart law and the principle of vector superposition. The quantitative numerical calculation is first performed for a single oblique winding coil having a small pitch and the corresponding magnetic induction lines are plotted, which is consistent with that of an ideal coil. Same calculations are carried out on the magnetic field of a single oblique winding coil and multi-turn coils with external lines. The influence of the number density of coils and the length of solenoid on the magnetic field are discussed in detail. Compared with the magnitude of magnetic field at center of solenoid with length L=200mm, the variance of magnetic field at range of -0.3L≤z≤0.3L is less than 4% which can be regarded as a uniform magnetic field, when the number density of coils is greater than 10mm^-1. The results in this paper can improve the independent scientific research ability for undergraduate students and provide intuitive and clear teaching materials for theoretical and experimental teaching in college physics.