Problem Solving

[learner27]

Hello Guys thanks for opening up this topic so here it is:

 

1) An ultrasound scanner is being used as a sonar device to locate a metal fragment embedded in patient. The method is to produce a sound pulse and time the echo from the fragment (pulse-echo technique) if the sound speed in tissue is 1500m/s and the time from the pulse to echo is 4 microsecond , what is the depth of the fragment?

 

When i analyzed this problem, i first thought about the Sy , as the one that is looking for, but im not really sure please help me guys thank you

[Iota]

1) An ultrasound scanner is being used as a sonar device to locate a metal fragment embedded in patient. The method is to produce a sound pulse and time the echo from the fragment (pulse-echo technique) if the sound speed in tissue is 1500m/s and the time from the pulse to echo is 4 microsecond , what is the depth of the fragment?

 

Show us what you think you might have to do (your working out). We can't just give you the answer.

 

 

When i analyzed this problem, i first thought about the Sy , as the one that is looking for, but im not really sure please help me guys thank you

 

What's the Sy?

[learner27]

ohh.. yeah Sy is the y, meaning the length,, the ahmmm... the length yeah it is the length

[JMJones0424]

You're given a speed (distance/time) and a time, and you need to determine a distance. Get your units sorted out and it should be pretty straightforward.

[learner27]

yeah i gigured that i should use this formula

S=Vit+1/2at^2

or

S= Vf^2-Vi^2/2a

 

but i dont have the acceleration.. i dont know what to do

[JMJones0424]

Are you sure you aren't making this far more complicated than it is? The scanner sends a pulse of sound, it bounces off the metal, and then arrives back at the scanner. You know the speed that the sound moves and the amount of time it takes to go to the metal and return to the scanner.

 

[math]speed = \frac{distance}{time}[/math]

[math]distance = speed \times time[/math]

 

You need to convert microseconds to seconds and then just do the math to find the total distance traveled by the sound pulse (scanner to object and then back to the scanner). Then cut that in half to find the distance from the scanner to the metal object.