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Pie
3 years ago
14

An ultrasound unit is being used to measure a patient’s heartbeat by combining the emitted 2.0 MHz signal with the sound waves r

eflected from the moving tissue of one point on the heart. The beat frequency between the two signals has a maximum value of 520 Hz. What is the maximum speed of the heart tissue?
Physics
1 answer:
Rus_ich [418]3 years ago
6 0

Answer: v= 0.2m/s

Explanation:

from Doppler effect

f = (2v/c) * fo

where:

f = the max beat frequency between two signals

fo = the emitted signal frequency from the organ.

v= The max speed of the organ tissue

c= 1540m/s (speed of Ultrasound wave in human tissue)

substituting the values, we have

520 Hz/ 2000000Hz = 2v/1540m/s

simplifying,

2v = (520 x 1540)/2000000

2v = 0.4004

v = 0.4/2 = 0.2 m/s

The max speed of the heart tissue is 0.2m/s

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