Spotted on one of the hand-outs that was dispersed last week:

I’m starting to think I’ve had (another) stroke.

It reads: “Is this true or false? Relative to ultrasonic testing, air is considered a good conductor and for this reason ultrasound will carry long distances in air.”

First, “relative to ultrasonic testing”? Not sure what that might mean.

Second, no, air is a rather horrible conductor of ultrasonic sound energy.

It reads as “TRUE – Relative to ultrasonic testing, air is considered a good conductor for this reason ultrasound will carry long distances in air.”

Uh… no, it isn’t and, no, it won’t. Air (of any kind or density) is an absolutely horrible sound transmission medium.