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Q: Units - Printable Version

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Q: Units - Dirk. - 09-09-2016 03:21 PM

I did some experiment with constants and units in CAS-Mode but did not understand the result. Could somebody please explain:

entered 1/SQRT(E_0*µ_0) without units and got 299792458, which seems to be the speed of light -> correct. (Of course SQRT ist the squareroot-key and everything is printed nicely on screen)

Tried the same _with_ the built-in constants and units:
SQRT(8.85..._F/m *1,2..._H/m)

leads to 8.98E16_m²/(F*H)

It seems to me, the square-root did not get evaluated...

Adding MKSA() into the root gives 8.98...E16_m²/s²

sqrt(8.98...E16_m²/s²) again leads to the result I expected in first place. The speed of light with correct units...

can somebody please tell me what I'm doing wrong?

RE: Q: Units - Dirk. - 09-09-2016 03:35 PM


in home it gives Error: Invalid input. But when adding MKSA() into the square-root, it works correctly.

RE: Q: Units - Dirk. - 09-13-2016 10:37 AM

... well, as can be shown using "Get from home"/Get from CAS, it is simply a bug of the CAS. It does not process the root and gives a wrong result.