大家有無咩關於physics嘅問題但又無地方問

唔識反彈嘅果然翁 2021-6-29 20:12:29 係你啱

:^(

唔識反彈嘅果然翁 2021-6-29 20:30:00 https://physics.stackexchange.com/questions/259759/conservation-of-energy-vs-expansion-of-space
But 我見呢個 answer係話Hamilton 同 conservation of energy 係 locality 而total energy of the expanding universe (a(t)^3 dependent) 係0?

:^(

我聽日同我個astrophysics professor 8下先

:^(

𝐸=𝑀𝑐2+Γ𝑎+Λ𝑐2𝜅𝑎3−3𝜅𝑎˙2𝑎−𝐾𝑎=0

唔識反彈嘅果然翁 2021-6-29 20:35:10 雖然我覺得個answer 最大問題係點解Dark energy 會係volume dependent同埋佢點樣同normal matter (radiation energy loss due to red shift) interact in a manner that it achieve a balance

:^(

Levicorpus 2021-6-29 20:48:03 簡單講就係距離比你同地心更遠嘅地球外殻唔會向你施加淨力，如果喺地球正中心掘就會係無重狀態

Shell_theorem

sparda 2021-6-29 20:54:58

如果prove到牛頓定律係錯成個physics係咪就會推翻晒？
:^(
咁你當佢已經被推翻咗啦
:^(

newtonian mechanics只可以準確描述較慢（eg.車、飛機、麥巴比）同較大（eg.人、黃豆）嘅嘢
快到接近光速要用相對論、細到電子咁就要用QM

:^(

街頭詩人.羅方 2021-6-29 21:00:13 咁Fission係咩力對抗binding force?

同埋fusion嘅energy release都係嚟自唔見咗嘅mass
咁點解Fusion又可以講binding force

:^(

唔識反彈嘅果然翁 2021-6-29 21:11:18

:^(

Fusion 係當個粒particle reach critical temperature 既時候透過quntum tunnelling 令到個 distance between 2 particle < d(crit)
<-呢個就係同bonding energy 有關

而nuclear fission 係透過加proton 令到個particle 唔stable從而引發nuclear decay breaking the bond

啜IU腳指 2021-6-29 21:13:11 現今科技可以製造寶石？

街頭詩人.羅方 2021-6-29 21:14:43 咁Fission係咩力對抗binding force

:^(

鋼之鍊金術師 2021-6-29 21:17:01 現實唔係佢呢個咁簡單嘅detector
我見過可以detect一個proton穿過邊個slit嘅實驗全部都係好煩用polarization又好用半透鏡又好最後其實係正常解到點解冇interference
因為個detector嘅setup影響咗啲proton 所以結果改變咗
但而家個個都話observation leads the wave function collapse 條片仲話解到可以拎到Nobel prize
我真係唔撚明

:^(

信長之北野望 2021-6-29 21:19:28 nucleon入面嚟講，痴埋係靠strong interaction, 彈開係因為EM interaction
應該係

掟上令日子 2021-6-29 21:19:57 即係我地個世界係虛擬?

街頭詩人.羅方 2021-6-29 21:36:34 可唔可以講多少少
點解Fission會有一種力可以大過強力

:^(

Betandbet(要贏) 2021-6-29 21:43:54 relative speed

信長之北野望 2021-6-29 22:22:01 電磁力，protrons之間正正相斥，所以愈多protrons就愈唔穩定
利申無追上面講咩，以波論波only

想起他蕉都興奮 2021-6-29 22:44:59 sor原來我一直調轉咗嚟講

:^(

fusion係mass轉咗做energy

fission先係分裂過程release energy
唔關mass defect事

fission純粹係因為nucleus太大粒
開始唔夠力hold住
當有particle大力撞擊佢佢就會分裂
分裂成幾粒細嘅nuclei之後
本身proton repulsion嘅PE放走咗

利申工程撚
nuclear phy得中學雞程度

DLLMEAA 2021-6-29 23:01:13 其實左同中應該係一樣?印象中只係stoke theorem轉一轉,右邊就唔識了,我ee major的

:^(

信長之北野望 2021-6-29 23:10:49

:^(

我諗應該fusion同fission都關Binding Energy事
Binding Energy係指拆開一個Nucleon需要嘅能量，同時亦係組合一個Nucleon放出嘅能量。
無論左去右定右去左都會放Energy，直到變成鐵。

我睇緊呢條片講得幾好，不過印式英文有啲聽唔明

:^(

https://www.youtube.com/watch?v=BYRz_9wvJzA

街頭詩人.羅方 2021-6-29 23:12:47 我背景同你一樣
所以我幾肯定你concept唔太啱

:^(

//fission先係分裂過程release energy
唔關mass defect事//
如果唔關mass defect事
咁release出嚟嘅energy來自邊度?
Proton之間嘅Electric Potential Energy夠咩?

//當有particle大力撞擊佢佢就會分裂
分裂成幾粒細嘅nuclei之後
本身proton repulsion嘅PE放走咗//
但係我記得加neutron嘅目的唔係撞擊佢
而係改變佢嘅Mass number
從而改變Physical Property (加強Radioactivity)
最後更易Fission

:^(

信長之北野望 2021-6-29 23:17:24 睇印度佬條片
強烈推薦，除咗口音之外無嘢輸

:^(

https://www.youtube.com/watch?v=BYRz_9wvJzA