香港天文論壇

明珠台既trick of mind？？
個主持好犀利
乜都俾佢知道

我都係新手
想問要影星座
要曝光幾耐
我既相機既f 有35-70mm

左上角係咪三裂星雲？？

唔係好識
我估係仙女座大星系

then how to calculate the momentum of light??
and why photon has momentun in the abscence of mass??

Me too
but I really wander how the ppl can score very high marks in the game

Is there any course that provide to adults??

I think I really cannot see stars in HK all the time because it is inconvinence to go to countryside without cars. Also HK urban area has too much 光害, makes me see too little stars.

小弟冇乜讀過物理學，宇宙中唔係所有野都有Mass嗎？光子是冇Mass定係Mass細到接近零呢？唔係玩野，真係唔識，懇請指點！

Me too ar
I feel very helpless when they talk about the physics
(Fail in AL physics)

光子的確是沒有mass的, 但有趣的是它有momentum

Then how photon can apply (mv-mu)/t???

Can ~Sun~ explain more about 4 dimensional pls??

一條都唔識
我對各位的物理知識佩服得五體投地

You guys and girls are pretty smart
The question seems simple
but The answer is increditable
Thank you all so much

Just register today
I hope I can gain more knowledge in Astronmy

I Agree
As a beginner, I always confuse in the phy theory