> The point that I am trying to make is that it is the >ratio of the mass of the objects and the duration of contact that determines >whether the energy transferred will in fact cause translation, rotation or a >stress disturbance in the oject tself. > For example, a mosquito hitting head on an aircraft carrier travelling >in a direction opposite to it when both are travelling at thirty miles an hour >will not in any way affect the velocity of the carrier even though their >closing speed is 60 miles an hour, notwithstanding vector addition, because >the energy of the mosquito on a molecular and atomic level is not sufficient >to propagate a stress disturbance through the carrier that is adequate to >reorganize the individual vectors of the particules which comprise the >carrier. However, the particle velocity of some of the particles on the >carrier will be changed, they in turn transmit a change to others and thereby a >stress disturbance of limited duration passes through a part of the ship which >has gained a little bit of energy, essentially in the form of heat. The >mosquito however, will suffer profound change both in structure, that is as >deformation, and velocity as the vectors of the individual particles, so to >speak, overcome by those of the ship and acceleration occurs. The velocity of the aircraft carrier will be influenced because the mosquito has mass. That's pretty inescapable. The disturbance of the structure of the carrier will be localized as it is pretty quickly lost in molecular "background noise" and dispersed as heat, but the disturbance does take place. It's a matter of scale, as you said. The rough equivalent of the same event would be something considerably smaller than a grain of salt being dropped on a soundboard. In either case, the event has so little resemblance to a string driven soundboard as to be meaningless. I propose a more accurate analogy of your Mosquito being a British aircraft, which would much more closely approximate the initial energy transfer between a string and soundboard assembly. In this case, I suspect the collision of the Mosquito with the aircraft carrier will not only be clearly heard, but felt by the malingerers hiding out in the head. I suspect a transverse wave could be fairly easily detected in the hull as well. Ron N
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