Illustrations of the centimetre-gramme-second (c.g.s.) system of units : based on the recommendations of the committee appointed by the British Association 'for the selection and nomenclature of dynamical and electrical units' / by J.D. Everett.
- Joseph David Everett
- Date:
- 1875
Licence: Public Domain Mark
Credit: Illustrations of the centimetre-gramme-second (c.g.s.) system of units : based on the recommendations of the committee appointed by the British Association 'for the selection and nomenclature of dynamical and electrical units' / by J.D. Everett. Source: Wellcome Collection.
Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.
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![hence we must have i-n w This equation shows that, when the units are changed (a change which does not aflfect V, L, and T), v must vary directly as / and inversely as t; that is to say, the unit of velocity varies directly as the unit of length, and inversely as the unit of time. V Equation (1) also shows that the numerical value - of a given velocity V varies inversely as the unit of length, and directly as the unit of time. 7. Again, let A denote a concrete acceleration such that the velocity V is gained in the time T', and let a denote the unit of acceleration. Then, since the numerical value of the accelera- tion A is the numerical value of the velocity V divided by the numerical value of the time T', we have A^ V ^ a « T' li t V But by equation (1) we may write j ^ for -. We thus obtain A _ L ^ J_ a ~ / T T'^ ' This equation shows that when the units a, I, t are changed (a change which will not aflFect A, L, T, or T'), a must vary directly as I, and inversely in the duplicate ratio of t; and the A . numerical value — will vary inversely as /, and directly in the duplicate ratio of t. In other words, the unit of acceleration varies directly as the unit of length, and inversely as the square of the unit of time; and the numerical value of a given acceleration varies inversely as the unit of length, and directly as the square of the unit of time. It will be observed that these have been deduced as direct consequences from the fact that [the numerical value of] an acceleration is equal to [the numerical value of] a length, divided by [the numerical value of] a time, and then again by [the numerical value of] a time. b2](https://iiif.wellcomecollection.org/image/b22295641_0017.jp2/full/800%2C/0/default.jpg)
