Jess Gonzalez asked:
What would happen if one was to pluck a guitar string in outer space?
Felicity Bedford spoke to Jim Woodhouse from Cambridge University's Engineering Department to find out...
Jim - You normally hear a guitar because the vibrating woodwork alters the air pressure Ė alternately compressing and rarifying it. Those pressure changes travel through the air as sound waves. Once they get inside your ear they cause vibration in your inner ear, which gets turned into electrical nerve impulses, which travel to your brain.
Felicity - Simple enough, Now say we were to blast off into space with our acoustic guitars, would we have any luck?
Jim - There can be no sound in space because thereís no air to transmit the sound waves. So if your pluck an acoustic guitar in space, the strings in the guitar body will vibrate roughly the same as the would on Earth, but no sound will be made.
Felicity - But , if no energy is being lost as sound waves, does this guitar string vibrate forever?
Jim - The string will vibrate for a little bit longer than usual because energy is not being carried away in sound waves, but it wonít be very different. Most of the energy goes into internal friction in the wood of the guitar body and that will still be the same. That energy simply turns into heat in the wood.
Felicity - So, if you find yourself floating in space, happily playing a guitar, will you ever know if your music is any good?
Jim - If our spaceman could manage to make a mechanical connection to the vibrating woodwork, they might get some sound transmitted via bone conduction, which is when sound vibrations travel through your bones to your skull and reach your inner ear that way. When Beethoven was deaf he managed to hear his piano by fixing a piece of wood to it and gripping it in his teeth. That wouldnít be easy to do while wearing a space suit.
Felicity - Thanks Jim. Although that doesnít bode well for our space jam, what about on the international space station, which, fortunately, contains air? The space boffins have been hearing from a real astronaut, Tim Peake who is set to launch this month.
Tim - So no, there is a guitar on board and of course Iíll be playing, I love to play but Iím not sure Iím ready to release my skills to the world yet.
Richard - So you wonít be sharing that?
Tim - Never say never but Iíve got no intention to at the moment.
Felicity - Thatís a shame Tim because, as Andrea said on facebook, - Your music would be out of this world.