. Practical electricity in medicine and surgery. Fig. 8. Fig. 9. it is absolutely necessary to become acquainted with the subject,for many problems cannot be understood at all without intro-ducing the idea. The potential at a point near a body may bedefined in either of two ways: We may define it as the chargeon the body divided by the distance between the body and thepoint, or, we may define it as the work which would have to bedone on a unit of positive electricity in bringing it from an in-finite distance to the point in question. The former definitionfollows at once from the latter, which
. Practical electricity in medicine and surgery. Fig. 8. Fig. 9. it is absolutely necessary to become acquainted with the subject,for many problems cannot be understood at all without intro-ducing the idea. The potential at a point near a body may bedefined in either of two ways: We may define it as the chargeon the body divided by the distance between the body and thepoint, or, we may define it as the work which would have to bedone on a unit of positive electricity in bringing it from an in-finite distance to the point in question. The former definitionfollows at once from the latter, which is therefore the more gen-eral and the more preferable. Potential, therefore, is work done, and can be expressed inunits of work, or, if we use the so-called absolute system ofunits, to be hereafter described, we can express potential, or dif-ferences of potential, in centimetres—grammes. 14 PRACTICAL ELECTRICITY IN MEDICINE AND SURGERY. We spoke of determining the potential at a point by bring-ing from a distance a sphere charged with a unit
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectelectri, bookyear1890
