SO: v3 (Second Timers)

BATS INTRO:    A whisper spot in a building is caused by a domed roof reflecting, concentrating and aiming the “sound air vibration” to a specific place.

BATS INTRO:    Horseshoe bats are being studied by engineers at Virginia Tech to make more sophisticated nuclear submarine sonar. Why?  Because these bats navigate by sonar effortlessly in dense jungles and never bump into anything.

BATS INTRO:    Horseshoe bats can change the shape of their ears in a tenth of a second, 30 times faster than we can blink. It’s these super-speed ear changes that help pick up their returning sonar better which produces sharper images.

BATS INTRO:    Horseshoe bats emit their sonar blasts through spooky-looking ear leaves.

BATS INTRO: Scientists now believe that the horseshoe bat’s nose leaves are super-sophisticated ultrasound transmitters that aim their sonar precisely by changing the “shape” of the sonar sound that is traveling through them!

SOUNDS THRU SOLIDS:   When you speak into a string phone, the cup vibrates with your voice’s exact vibration rate. The sound vibration travels through the string which is a solid.

SOUNDS THRU SOLIDS:   Indians would put their ear to ground and listen for deer.  As deer were tromping by, it caused the ground to vibrate. The Indians could tell where the deer were by “listening to the ground.”  The vibration of the deer walking would move through the ground almost like a little earthquake.  They could hear the deer because the ground would vibrate the air and the air would vibrate their ear drum.  If you took away the air, they wouldn’t hear anything.

SOUNDS THRU SOLIDS:   The other tale of the string phone, of hearing through a solid, involves settlers listening for the trains.  They could hear trains miles away by listening to the railroad tracks because sound can travel so much faster through air than through a solid.

MOON EXPLOSIONS:  There could be a small explosion on the moon and an astronaut would not hear one single thing because something has to transfer the “sound” of the explosion.  There is no air on the moon to transfer the sound like we have here on earth.

SOUNDS THRU SOLIDS:    A large enough explosion on the moon could possibly be heard through your feet.  Your feet would vibrate the bones of your body and it would transfer right up to your inner ear. Then you would hear it–in theory—anyway.     (More on this in the next Core Video.  You’ll be very surprised!)