Scales (Slide Rule): Difference between revisions

811 bytes added ,  12:50, 7 August 2023
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added section on alternative decimal point tracking.
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Therefore 3.67x10⁻¹ = 0.367
Therefore 3.67x10⁻¹ = 0.367
</syntaxhighlight>Notice here that we move ''down'' the rule from 4.31(D) to 3.67(D), which prompts us to add 1 to the characteristic.
</syntaxhighlight>Notice here that we move ''down'' the rule from 4.31(D) to 3.67(D), which prompts us to add 1 to the characteristic.
==== Digit Tracking ====
An alternative to scientific notation which can sometimes be shown on slide rules presents the same ideas in a different form, using the fact that the order of magnitude of a product is either the sum of the orders of the factors, or one less than that.  This essentially presents the same method as the scientific notation method, but reversing the rules:  When the product ''up'' the rule from the multiplicand, subtract 1 from the sum of the magnitudes, and when a quotient is ''down'' the rule from the dividend, add one to the difference of magnitudes.  This method ends up using the exact same mathematical principles, but from a point of view that can sometimes be more intuitive to users, as it doesn't require remembering that single digit numbers have a characteristic of 0.


=== Folded and Split Scales ===
=== Folded and Split Scales ===