Calculation of frequency-triggering

[alexpea22]

I attend a music technology school, and I need to deliver in some papers tomorrow, answering several questions. I have problems understanding this one, however, and was hoping for some opinions:

"We usually describe sound in 3 dimensions. Time (s), Level (dB) and Frequency (Hz). How many milliseconds does it take to start the vibrations in a pianostring, in a trumpet-tone and in an organ-tone?"

1. I don't really understand the question here, cuz I don't know if the startpoint of the calculation should be upon the impact of the piano-key, or when the piano-hammer hits the string within the piano.

2. The trumpet is a littlebit easier, as it starts (I believe) when the first breath of air comes into the chamber. Then it's a matter of finding the frequency-response of a trumpet, and calculating the speed of sound together with the periodic swing, and the length of the chamber. However, I don't know the amount of reflections within the chamber before the sound reaches the end, so it seems impossible.

3. The organ-tone is also very absurd to me, as it's produced by electric signals. So I have to calculate the time from the triggering of the electricity, until the actual reproduction of sound from the internal speakers.

Hmmm...though one, this. I have no idea how to approuch it what so ever. Help :redface:

[Steerpike]

Maybe they are referring to the wavelength, and amplitude in relation to the resonant device's physial size.

For the organ, I understood it to mean pipe organ.