光子 有 mass 咩 ?

光子(量子囉)即係電磁波的一種
而電磁波係空間中以波的形式移動 傳遞能量和動量
在宇宙,有很多野係靜止質量為零的狀態下存在
光子 只係 運 動 果時先有 質 量
換句話說，這個世界上 不 存 在 靜 止 的 光 子 (即有質量啦)
而其質量就等於測定的能量
所以,無論如何,光子都有mass的

No. Photon has no mass.
To say an object has mass, we refer to the fact that the object has [rest mass], i.e. the mass the object possessed when it is stationary.
Photons can only exist when they are in motion and their speed in vacuum is just the speed of light. Photons cannot be brought to rest. They have no [rest mas].
Einstein's equation E=mc^2 only gives the [mass equivalence] of a photon with energy E. Mass equivalence is only a concept and which by no means indicate that a photon has real mass.

E=mc*c

光子有能量, 它可以用另一型式來表達, 就是重量.
您只須將光子的E除2次光速就是它的mass.

讀完書太耐了, 忘記它的E是多少,也忘了它的mass是多少? 您只要翻開任何一本大學物理學就會有的.