Galloway's schoolbook of useful knowledge / P.H. Galloway Ltd.

  • P.H. Galloway Ltd.
Date:
[1933]
Catalogue details

Licence: Public Domain Mark

Credit: Galloway's schoolbook of useful knowledge / P.H. Galloway Ltd. Source: Wellcome Collection.

    43/68 page 41
    “ pressure which will produce a current of one ampere against as _ fesistance of one ohm. -- Ohm—The unit measure of resistance offered to an alee current by a thread of mercury 106°3 cm. long and ]_ mm. cross, section at a temperature of 32° Fahr. a = _ Megohm.—One million ohms. __ Ampere-—The unit measure of current produced by a pressur of one volt against a resistance of one ohm. ~Coulomb.—One ampere flowing for one second. _ Wait—The unit of measurement of electric power equal to i ane 408 part of | horse power. Kilowatt—One thousand watts. B.W.G.= Birmingham wire gauge. — C.L.=cast iron. BEG C sdouble cotton covered (of wires). D. P= = double me:
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