ARDMS Ultrasound Physics & Instrumentation Practice Exam

Disable ads (and more) with a membership for a one time $2.99 payment

Prepare for the ARDMS Ultrasound Physics and Instrumentation Exam. Access flashcards and multiple-choice questions, each with hints and explanations. Boost your exam readiness!

Each practice test/flash card set has 50 randomly selected questions from a bank of over 500. You'll get a new set of questions each time!

Practice this question and more.

If the angle of incidence is 40°, what can be inferred about the angle of transmission when moving from a medium with a speed of 1320 m/s to another at 1700 m/s?

Equal to 40°
Less than 40°
Greater than 40°
Unpredictable

The correct answer is: Greater than 40°

When a wave passes from one medium to another, its speed changes depending on the physical properties of the substances involved. The angle of incidence and the angle of transmission (also known as the angle of refraction) are related by Snell's Law, which states that the product of the sine of the angle of incidence and the speed of the wave in the first medium is equal to the product of the sine of the angle of transmission and the speed of the wave in the second medium. In this scenario, when moving from a medium with a speed of 1320 m/s to another with a higher speed of 1700 m/s, Snell's Law illustrates that the angle of transmission must increase as the wave enters the second medium. This is because the sine function is increasing, meaning that if the speed is greater in the second medium compared to the first, the angle of transmission will be greater than the angle of incidence. Therefore, since the incidence angle is 40°, and the second medium is faster, the angle of transmission will be greater than 40°. This principle of refraction is foundational in understanding how ultrasound waves behave when they transition between different tissues or mediums, reflecting the principles of wave propagation and angle relationships in physics.