[TCML] Cm Vs Henry

[Harvey Norris <harvich@xxxxxxxxx>]

Found this reference;

TRANSTROM'S Definition of
UNIT VALUES Now concerning the use of inductance
defined in terms of cm , Transtrom also goes into this on pg 80-82. The
inductance of a
circuit is sometimes expressed in centimeters, one of
the cgs units or absolute units. By definition a circuit has a self induction of one henry when it generates a counter emf of one volt when the current is varied at a uniform rate of one ampere per second-- that is the circuit cuts 10^8 lines per second: so a circuit of one turn which has a flux of one Weber (10^8) when one ampere is flowing through it, has an inductance of one henry. One volt then represents a movement of a single conductor of 100,000 cm per second across a unit field (1 line per square cm) In this way the emf in volts can be
given the dimension of length, namely 10^8 cm. As a
circuit of one henry inductance generates a counter emf of
1,000,000,000 centimeters when a change of one ampere, or one tenth unit of current per second,it is plain that the counter emf would be ten times as high, or ten volts (1,000,000,000 cm) when the rate of current change per second is unity (or ten amps per second) Therefore one Henry of inductance
is given the dimension of 1,000,000,000 cm. In a
circuit of only one turn the inductance in centimeters can be directly obtained from the number of lines enclosed when a current of 10 amperes is flowing through the conductor. The Henry was once called the secohm, because a circuit having an inductance of one henry would only permit a rate
of change of one ampere per second when the impressed
current had an emf of one volt, and as the counter emf acted as one ohm resistance, we see from this that the inductance can be expresssed in ohms. The henry has also been called the quad, or quadrant because in the metric system a quadrant of the earth from the equator to the pole equals approximately 10^9 centimeters. Both terms mentioned above are now quite obsolete."
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