An Easy Method to Discuss Properties of Simplified Solid-state Tesla Coil
Wireless transmission products are widely used in our daily life. In this research, we focus on knowing how solid-state tesla coil works in different conditions and finding the best parameters through an easy way. In our work, a commercial electroscope was used as detector for measuring the strength of radio wave created by our simplified tesla coils. In fact, many factors would lead to experimental erorrs such as detectors, selected types of NPN BJT components, applied voltage and measuring position of height. Therefore, all of the factors were under control to make sure of accuracy and precision for our designed measuring method. In our experiment, graphics of radio wave distribution around tesla coils were drew by mathemetic software of GeoGebra. It shows the BJT types of 2n2222 had good performance for wireless transmisstion efficiency. To our surprised, we found the extended wires (called antenna) from the top of tesla coil also had an ability to transfer electromagnetic energy, and had good retention if the extended wires were within the length of main coil’s height. Finally, the shape’s and size’s effect was determined by our testing work. The result shows that pipe’s length, pipe’s diameter and turns ratio of two coils had great influence on tesla coil’s transmission efficiency. It was found that the tesla’s performance would be more efficient if wire was used to make the length twice rather than make the diameter twice. However, the turns ratio of secondary coil to primary coil would change while making the length twice. To avoid that, we fixed the length and decrease the turns of primary coil. At last, we found tesla coil must work at the turns of primary coil higher than two. Furthermore, the frequency of radio wave not only had less relationship with their length or diameter but also had less relationship with types of BJT In our study, our handmade tesla coil was succesfully applied for wireless charging and we find that the induced voltage decrease in propotion to cube root of distance between tesla coil and induced coil.
3進位Kaprekar變換之結構
b進位的n位數字x,數字x各位數字由大到小排列為p,由小到大排列為q,定義Kaprekar變換T(b,n)(x)=p-q,例如T(10,3)(x)= 954-459。當T(b,n)(x)= x,稱x為Kaprekar常數。 Tk(b,n)( x)=T(b,n)( Tk-1(b,n)( x))= x, k >1時,稱x為k階Kaprekar循環數。本文解答了以下問題: 1. b進位的數字不包含數字b-1的Kaprekar常數的形式。 2. 3,4,5,6進位的Kaprekar常數的一般形式。 3. 對於2,3進位的情形,我們引入三元非負整數的形式來討論Kaprekar變換,轉換成Kaprekar數對(p,q),再進一步,由來探討比值p/q,將Kaprekar變換轉成Kaprekar函數g(x),解決 Kaprekar 循環數的所有形式及解。 最後我們得到Tl(b,n)( x)必是Kaprekar循環數。