(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Ultrasound waves are used to find the size of an unborn baby's head. Echoes are recieved from the front and the back of the skull bone. The reflected sound pulses are detected and displayed on an oscilloscope screen that shows that the echoes are 0.15ms apart. If the speed of the ultrasound waves through the baby's head is 1400m/s, calculate the diameter of the bay's head. Remember that reflected waves travel twice the distance.

2. Relevant equations

v=f[tex]\lambda[/tex]

speed=distance/time

3. The attempt at a solution

So when they say that the echoes are 0.15ms apart, does this mean on the baby's 2 sides of the skull or is it the wavelength of the ultrasound?

1400=f[tex]\lambda[/tex]

what's the wavelength, and are we supposed to assume frequency is 6.0x10^4Hz?

so this is where i'm stumped. I'm obviously very wrong, i Know.[tex]\lambda[/tex]

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# Homework Help: Ultrasound to Find Diameter

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