Understanding Systems?!?

Question

Explain why ultrasound can be used to make an image of soft tissues, while X-rays are used to make images of hard tissues.

Answer 1

In ultrasound, the imaging is based on echoes of acoustic waves (though in the megahertz range), which travel well without much attenuation through liquids and "squishy stuff" like organs. But this acoustic energy tends to be absorbed by solids such as bone.

X-rays can be used for both soft and hard tissues, depending on the kilovoltage, but have the disadvantage of permanently damaging DNA. So x-ray tends to be used where ultrasound can't get the desired info, as in displaying thin bone fractures or imaging of the lungs where the ribs block ultrasound.