Question

- The wave used in the sonography is –
A) Infrared waves
B) Microwaves
C) Sound waves
D) Ultrasonic waves

Answer 1

Hint: Sonography is used in medicine for diagnosis and gives output of the dynamic visual images of the organs inside our body by using the high frequency waves. This is also known as sonogram.

Complete step by step answer:
Sonography can be defined as a medical technique which is used to produce visual images of organs of our body. It can also show blood flow inside the body by using sound waves of high frequency. Now, we have four options given in the question. So, let’s see which one of them uses high frequency sound waves –
The electromagnetic waves that wavelengths longer than visible light are known as infrared waves. The frequency of infrared waves ranges from about 300 gigahertz to about 400 terahertz. Its wavelengths range from about 1000 micrometers to 760 nanometers.
Micro waves are also a type of electromagnetic radiation which frequencies ranging between 300 MHz and 300 GHz. Wavelength of microwaves is estimated to be about 1 meter to 1 millimeter.
Sound waves are the mechanical waves which are produced by the vibration of particles of the medium. Sound which is precipitable by humans have frequencies ranging from 20 Hertz to 20000 Hertz.
Ultrasonic waves are the sound waves which have high frequencies. The frequency of these waves is higher than the upper audible limit of the humans. The frequencies of these waves is from 20 Kilo – hertz to several gigahertz. These waves are used in measuring distances and also used for detecting objects.
Now, from the above discussion we can conclude that ultrasonic waves have the highest frequencies of all others. They are used for detecting objects. As sonography requires the waves which have high frequencies and can detect objects, the ultrasonic waves are suitable for sonography.
Hence, the correct option is (D).

Note: Ultrasonic waves in medical is also used echocardiography and is also used to remove cataracts. This wave is used in Sound Navigation and Ranging (SONAR) to detect objects and distances under the water.