In: Physics
A doppler meter of frequency 3 MHz (accurate to +/ - 10 Hz) is used to monitor the heart rate of a fetus in early pregnancy (8 – 10 weeks). Determine the maximum positive and negative shift in ultrasound frequency detected by the meter due to the heart motion. For a simplified model, take the main fetal heart muscle to move like a mass on a spring undergoing Simple Harmonic Motion, with a maximum distance (amplitude) x max = A = 1.0 mm and a frequency, f = 150 beats/min. Take the speed of ultrasound in the body to be v =1540 m/s. Method: write a sine function that describes the motion of the heart muscle. 2.determine the maximum positive and negative velocity of the heart muscle by differentiating your equation 3.use the doppler equation to determine the corresponding frequency shifts.