A specific part of engineering course at Cambridge in the 50"s was a clear
grasp of the order of magnitude of things, it has stood me in good stead in all
matters from ham radio thro' yacht navigation quite apart from earning a
living..
bryan G3GVB
Quoting John Rabson <[email protected]>:
On 19/11/2004 at 08:13 Andy wrote:
>When it comes to calculations, the most useful ability is not to be able
>to
>caculate it exactly, caculator or no, but to quickly be able to estimate a
>ball
>park answer or approximation.
>
>Who needs to know that 22uH at 137kHz has 18.93 ohms reactance.
>
>Its quicker to think " a bit more than 20 times a bit less than 0.14,
>times
> 6-and-a-bit
>... is 2.8 times 6-and-a-bit , so call it 18 ohms"
>
>And they don't teach that in schools - and never have done, to my
>knowledge!
>
>Andy G4JNT
I seem to recall a telecommunications professor (Ken Cattermole?) who
expected his MSc students at least to have a feel for whether a result was of
the right order of magnitude.
John G3PAI
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