answers ;) (1 Viewer)

[beemz]

jacaranda, hsc, physics 2, text book

does any one have the answers to the questions?...
it has answers for mathematicla stuff but not the knowledge and some info isnt in the book anywhere....
...mso... if anyone... does... who would like to post/send them...
..or just exchange answers that could be helpful too

ill start one...

er... q.18 (b), um ultrasound, p357
give two reasons why the amplitude on a cro for a-scan varies...

well..
(1) obviously, the reflected intensity varies for each boundary due to the differing acoustic impedance
(2) ???? aarrgh! wah? :s

mm.. feel free to fill in (2) and correct my (1) if you see a fault

thanks

looking forward to some replies

 

[sinist4]

hey... i cant do that one, im not doing the age of silcon
LOL

btw do you hav cssa physics tmr ?

 

[beemz]

lol..
right..

ah yes, yes i am doing the cssa physics tomorrow!
how did you know? *suspisious*


errrrr.. outline the property of electrons that allows them to be focused isng electric and magnetic fileds but prevents x-rays frombeing focused.... !!!!


:S:S:S:S:S

 

[helper]

1 looks right.
2 Could mean a number of things but in order of most likely:
Sound waves are attenuated by the material they are passing through, so the signal will be weaker the more material it passes through.
Reflective surfaces are not always perpindicular to the signal wave, so the reflected wave is not all reflected back in direction of transducer. This results in scattering.
The sound wave is a 3-D wave, so it decreases in amplitude with d^2, so further away sound is reflected from,. the weaker the signal.

Haven't got my version of Jac here, so I can't check if its in there.

 

[beemz]

that is great!! thankyou so much!
if i could afford it, if knew you and i was legal, id buy you a drink