Sound Questions

• Can sound waves generate heat?
• Can wind travel faster than the speed of sound?
• Does sound travel faster in space?
• How does sound going slower in water make it hard to talk to someone underwater?
• What psychological effect makes notes on a piano that are an octave apart sound the same?
• When I bump one end of a long metal bar, the other end instantaneously moves. Can I use this to send messages faster than light?
• Why are sound waves invisible?
• Would a guitar sound the same on a space station?