為何電子會自轉及環繞著原子核公轉?

In fact, in quantum physics, there is no physical spin or rotation of electrons around the atom, from the uncertainty principle, the electrons do have a probabilitly distribution with magnetic properties called as ' spin ' .
You can find electrons any where in the atom, by a probability, the ' orbits ' are the peaks of the probabilitly distribution, you can find electrons more easy there.
There is energy state of the electrons in atom, these energy is the KE + PE of the electrons, PE is the protentail energy of the elctron in the eletromagnetic field of the atom. The KE you ask are come from PE. Please remind that the classic physics cannot be apply in quantum world.

與行星圍繞恆星轉動的原理一樣，但這是因為恆星的重力將時空扭曲而令行星向它們運動，電子圍繞原子核轉動則是因為電磁力。原子核有質子，質子帶正電荷，電子帶負電荷，你也應該知道正負電相遇會怎樣吧！電子一遇到有質子的原子核，就會因為磁性之異而相吸，所以就圍繞着原子核旋轉了！