宇宙裏是不是很寧靜,聽不到任何聲音?點解?

sound can only travel through a medium, without a medium, sound cannot be transmitted.
Since space is a vacuum (almost a vacuum), there is no media where sound waves can be transmitted, therefore, there is generally no sound in space. BUT, theories have shown that space is not a complete vacuum, meaning there is the presence of dark matter, however, since no one knows what dark matter is made of, no one can be sure if it can transmit sound waves. Even IF dark matter can transmit sound waves, since its density is so little, like you said, the sound waves will be very 低頻率.

2006-12-10 10:32:48 補充：
sound does not have to be transmitted through air, sound waves are just the collisions of particles, so sound waves can be transmitted through liquid and solids also

2006-12-10 10:33:01 補充：
in fact, sound travels faster in solids than gas because solids are more dense, making the particles more elastic, thus the particles collide faster and transmit sound waves faster.

This is beacuse there is no air in space. Since sound wave is a kind of mechanical wave, it requires a material medium for propagation. This is why you can't hear any voice in the space.

我想是!因為聲音需要介質振動來傳遞，如水、空氣等。太空中沒有這一類的介質，所以人類聽不見聲音。

很寧靜,聽不到任何聲音,冇人聽到ge粒子振動

因為宇宙裏沒有作為聲音傳播的媒介-------空氣,聲音是以聲波形式傳播的,若找不可以被它依附的介質,就不能傳播.

正確來說, 太空是寧靜的(不能說是宇宙)
因為聲音是由空氣用媒介
以波動形式(震動空氣中的粒子)而傳播
而太空中因為引力的問題
空氣粒子會被星體吸引而形成大氣層
所以空氣粒子不存在於太空
故此, 太空是寧靜的

宇宙含意太廣, 指的包括太空+星體
星體中有空氣的
因此不能說宇宙是寧靜, 只能說太空是寧靜的

Because space doesn't air so our ear can't hear anything.

Because there have no air in the space!!!!!