Q.1
Which of the following is/are advantages of ultrasound used in medical scanning?
  • Non invasive - it is all done from the outside of the body
  • Inexpensive compared to other scanning methods
  • It is non-ionising
  • All of the above
Q.2
The speed of ultrasound in metal is 5,000 m/s. How far away is a crack in the metal if an ultrasound wave is sent through the metal and is reflected back from the crack to the detector in 0.01 ms?
  • 0.025 m
  • 50 m
  • 50 cm
  • 25 cm
Q.3
Which of the following statements is correct?
  • Ultrasound waves are partially reflected when they are incident upon a boundary between two different mediums. The time it takes for the reflections to hit a detector can be used to determine the distance the boundary is from the detector
  • Ultrasound waves are fully reflected when they are incident upon a boundary between two different mediums. The time it takes for the reflections to hit a detector can be used to determine the distance the boundary is from the detector
  • Ultrasound waves are partially reflected when they are incident upon a boundary between two identical mediums. The time it takes for the reflections to hit a detector can be used to determine the distance the boundary is from the detector
  • Ultrasound waves are fully reflected when they are incident upon a boundary between two identical mediums. The time it takes for the reflections to hit a detector can be used to determine the distance the boundary is from the detector
Q.4
Which of the following are medical uses of ultrasound?
  • Pre-natal screening
  • Breaking down kidney stones
  • Neither of the above, X-rays are used
  • Both of the above
Q.5
Which of the following can be a use of ultrasound waves?
  • Sonar
  • Animal communication
  • Fetal scanning
  • All of the above
Q.6
What is the frequency above which a sound wave is known as ultrasound?
  • 5,000 Hz
  • 10,000 Hz
  • 15,000 Hz
  • 20,000 Hz
Q.7
Ultrasound waves travel approximately 1,500 m/s in water. A boat sends out an ultrasound wave to the bottom of the ocean. It takes 0.5 seconds for the wave to hit the bottom of the floor and reflect back to the detector. How deep is the ocean floor below the boat?
  • 350 m
  • 375 m
  • 500 m
  • 675 m
Q.8
The speed of ultrasound in air is 330 m/s. How far away is a car if an ultrasound wave is sent to it along a road and takes 0.1 s to return?
  • 10 m
  • 14.5 m
  • 16.5 m
  • 20 m
Q.9
Which of the following is/are disadvantages of ultrasound?
  • Limited resolution
  • Reflected strongly when passing from tissue to gas
  • Does not pass well through bone
  • All of the above
Q.10
Which formula correctly relates speed, distance and time?
  • Speed = Distance x time
  • Distance = Time/speed
  • Speed = Distance/Time
  • Speed = Time/ Distance
0 h : 0 m : 1 s