Ultrasounds Flashcards
What is ultra sound
Sounds that vibrate at frequencies above 20,000 Hz
(Above the range of human hearing)
What animal produces ultrasound naturally and what for?
Bats
For communication and echo location
What happens when ultrasounds hit a boundary between different medians
Some waves will be reflected
Some will be transmitted through and refracted
‘ partial reflection’
If we know the speed of the wave and the time it takes to be reflected, what can we work out?
How far away is that Boundary is
(Tell us about its internal structure of an object )
(Or how far away to sea floor is)
If we know the speed of the wave and the time it takes to be reflected, what can we work out?
How far away is that Boundary is
(Tell us about its internal structure of an object )
(Or how far away to sea floor is)
What is one benefit of ultrasound waves?
They’re completely safe no radiation
How are ultrasound waves used to scan a foetus?
Play Sinatra sound device onto a pregnant woman’s body
Fire ultrasound waves towards the fetus
Every time waves hit a different medium some waves are reflected back to the device
The timings and distributions are then processed by computer
This produces a live image of the fetus
Why are ultrasound machines used?
To check if the babies healthy
What are three main uses of ultrasound waves?
Ultrasound machines (baby scanning)
Check quality of products in industry
Echo sounding
How does checking the quality products in industry work?
If an object should be completely solid
We can fire waves to see if they are only reflected at the start of the end of the object
If there’s an empty (crack,hole) reflect back
We can then tell if there’s some kind of fault
How does echo sounding work on boats ?
When boats/submarines want to check the depth of the water
We can fire ultrasounds at the floor to find out how far away they are
What equation would you use for echo sounding (finding out how deep the water is)
Distance = speed x time
