Draw diagrams to show the first three modes of resonance in the following instruments (also find the frequencies of these modes if the air temperature 20 °C): a) A clarinet 75 cm long that functions acoustically like a closed air column.
b) An organ pipe open at both ends that is 4.8 m long.
c) A guitar string 1.3 m long with a wave speed of 66 m/s.

It may seem strange that the selected velocity does not depend on either the mass or the charge of the particle. (for example, would the velocity of a neutral particle be selected by passage through this device? ) the explanation of this is that the mass and the charge control the resolution of the device--particles with the wrong velocity will be accelerated away from the straight line and will not pass through the exit slit. if the acceleration depends strongly on the velocity, then particles with just slightly wrong velocities will feel a substantial transverse acceleration and will not exit the selector. because the acc