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2 years ago

7

An ultrasound pulse used in medical imaging has a frequency of 5 MHz and a pulse width of 0.5 us. Ap- proximately how many osci

llations of the sound wave occur in the pulse? The number of oscillations is sometimes called the quality, Q, of the pulse. A pulse with little damping has Q 1, whereas a heavily damped pulse has e 1. Is the ultrasound pulse heavily damped?

1 answer:

podryga [215]2 years ago

4 0

At the frequency of 5 MHz, the period of the oscillations is 1/5meg. That's a period of 1/5 microsecond.

There are 5 full cycles in one full microsecond, and there are 2.5 full cycles in a 0.5 us pulse.

You'll have to decide for yourself how damped a pulse of 2.5 cycles is, because the parameters of the definition are corrupted in the question.

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