The teacher probably meant that the capacitor with a reactance equal to the resistor will produce a half-power output from across the capacitor.
The voltage is at 0.707, therefore the output is 3dB down which is half-power.

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Uncle $crooge

 

Ron, no need to apologise!

Yeah the wording doesnt really specify the configuration, and i automatically assumed the high pass. So both answers are valid

Megamox

 

Len, I see you've been on this forum for 2 years. You need an avatar so we can more easily spot your posts, and also to see what sort of foolish picture you select for it. :lol:

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Ron

 

Audioguru, I agree - but that's apparently not what he said (unless he was misquoted, which is entirely possible, since we're getting it third hand).

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Ron