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Name: David
Status: student
Age: 13
Location: N/A
Country: N/A
Date: 1999 


Question:
I've always been fascinated by the realism of movies like Star Wars. For a start, it just recently annoyed me in the sci-fi movie "Wing Commander" that when an enemy spaceship passed over theirs, they told someone to be quiet or else they'd be heard. I thought sound doesn't travel in vacuums. Is that true?


Replies:
It is true. Sound needs a medium through which to travel. It will not travel in a vacuum. It is OK to be annoyed. Though perhaps they were speaking of radio silence - radio waves do travel in a vacuum.

Larry Krengel


That is correct, sound needs a media to propagate. Sound can not propagate in a vacuum. Sound waves, unlike light, are essentially compression waves and the sound in order to move from one place to other needs molecules to compress and decompress against, hence the wave is transmitted. In a vacuum, there are no molecules. Hence no sound. Star wars the movie is still fun.

Dr. Myron


Movies are made to be entertaining, not realistic. In Star Wars Episode 1, I noticed among other things that the battle droids' command ship broke apart and fell downward when it was destroyed by the heroes. There would have been no reason for it to fall down; it was already in orbit, and noting was holding it up that was removed when it was hit. But, it looked cool, and it was a nice special effect.

You are quite correct, there is no sound in a vacuum. So "Wing Commander" has some careless writing. I think I'll have a heart attack and die from that surprise.

Richard Barrans Jr., Ph.D.



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