If a tree falls in the forest and there's no one around to hear it, does it make a sound?

Question

I've often heard this question asked, but don't believe I've ever been given a good answer to it. Can anyone out there change that?

Answer 1

According to the laws and definitions of acoustics, three items are necessary for the production of sound: a source, a medium, and a recipient. In the given example, the first two requirements are met, but the absence of a recipient (human ear) dictates that no sound occurs.

Answer 2

No.

By most understanding of physics, it has mass, it falls, it hits the ground, it causes vibrations whether or not there is someone to measure it. Pat answer is Yes.

However, if there is no measurement, how can you be sure? Maybe this time, there was no sound. Does the measurement define the sound? If the tree falls and I come around to see it later, it seems pretty quiet. We can take it to another level... an event happens 50% of the time. I flip a coin behind a screen without looking. Is it heads or tails?

Answer 3

Yes, a sound is made. Sound is just a variation in air pressure, in this case triggered by the event of the falling tree. There is nothing in the definition of sound that needs an ear to hear it -- the variation in air pressure is enough.

Answer 4

yes, to prove that it does. . . wait until a wind storm is getting near. Cut the traa so that it will fall with the strong winds and set a tape recorder near the tree. . . . if the tree doesn't fall on the recorder, you'll have your answer.


(but the answer is yes, it does make a sound.)

Answer 5

My friend "sound" is a term we gave in order to understand the true meaning of why our eardrums vibrate when masses collide.
When masses collide that cannot be percieved they are creating waves that travel throught the air until receptors or senses can perceive them.
Evolutionary processes have given mankind and life forms, the ability to detect these waves, especially to keep you from wandering underneath one of these trees.
So yes waves (sounds) are created, you just have to be there to detect them.

Answer 6

It all depends upon how you define sound.
If you define it physics-wise as something that causes vibrations/compression waves in a medium (such as air), then yes it makes a sound.
If you define it biologically as something that is perceived by the auditory sensors/receptors of an organism, then no it did not make a sound.

Answer 7

Yes it makes a sound. Animals will be startled. It is a zen question to clear the mind. Just because you can't hear it, doesn't mean that it didn't happen.

Answer 8

No

sound is what we perceive, its in our brains, not out there

there would be vibrations through the various media in the area, the air particularly, but no sound

Answer 9

It makes a sound but no one heard it.

Answer 10

Yes, it makes a sound.