Calculating the diameter of baby's head

[rittahbee]

Calculate the diameter of a baby’s head if there is a time delay of 85 microseconds between receiving pulses from either side of the skull, and the speed of ultrasound can be assumed to be 1250 m/s.

I did some calculations which came to 5.3125 cm which doesn't sound right to me.
Distance = Speed × Time Distance = 1250 m/s × 85 × 10^-6 s Distance = 0.10625 m
Diameter = Distance / 2 Diameter = 0.10625 m / 2 Diameter = 0.053125 m or 53.125 mm

 

[BvU]

Hello @rittahbee ,

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