Blog

Artifacts may appear in ultrasound images when reverberations occur.

A wave with a frequency between about 20 and 20,000 Hz is a sound wave that is audible to the human ear.

An ultrasonic beam propagates from medium 1 into medium 2. If the incident angle is smaller than the refraction angle, the sound velocity in medium 1 is higher than that in medium 2.

When an ultrasound beam propagates from medium 1 into medium 2, it has 50% reflection. Assume medium 1 has an acoustic impedance of 1 MRayl. The impedance of medium 2 is:

The main reason of using ultrasound gel between a scanner and the skin is to allow the scanner to move smoothly on the skin.

Who usually elects the Board of Directors for a corporation? 

When a corporation sells stock to the public it is first done through what mechanism?

Which of the following foods is a good source of vitamin D for a school-age child?

If adults of legal drinking age choose to consume alcohol, the Dietary Guidelines for Americans recommend drinking in moderation, which is defined as

Which of the following is a dietary strategy that may reduce the risk of lead poisoning among children?