Slide Rule Free

A slide rule is a multi-purpose calculator tool. It looks like a ruler, but has a slide-y part in Slide Rule middle. You can use it to quickly multiply and divide large numbers, and if you are a slide rule whiz you can even do exponents, roots, and trigonometry. Slide rules can get very fancy, but the basic type has a bodyone slide the thing running down the middleand a cursor Slide Rule gives you a line so you can accurately line up the body and the slide with each other. See those letters next to each scale of numbers? To multiply or divide, we can use the C scale on the bottom of the slide together with the D scale Slide Rule next to it, on the bottom part of the body. Look at your slide rule. The C scale is on the slide, and the D scale is on the body. Now look at the numbers on each scale. There are In the example here, you can see the C and D scales both have the Slide Rule 1, then Slide Rule number 1 again, then numbers up through 9, and then, finally, 2. All of those numbers in between Slide Rule represent 1. Are you ready? Photos of each step are in the slideshow above. For more advanced calculations on the slide rule, and to read up on how a slide rule Slide Rule works hint: logarithms Slide Rule, we recommend this excellently nerdy page from the University of Utah. Beth is Lifehacker's Senior Health Editor. She has written about health and science for over a decade, including two books: Outbreak! Her Wilks score is Everything you need to know about and expect during. The A. Analog Week. Beth Skwarecki. Filed to: Slide Rule stuff. Analog Week Analog Week Just because 'there's an app for that' doesn't mean you have to use it. Prev Next View All. Beth Skwarecki Posts Email Twitter. Share This Story. Get our newsletter Subscribe. What's New on Netflix in November How A Slide Rule Works

There are many pages about slide rules on the Slide Rule, and you can still buy brand new slide rules 40 years old but never used, and still in their factory supplied box in various places. The purpose of this particular and quite idiosyncratic slide rule page is to describe common scales used on slide rules, and the kind of mathematical expressions that could be evaluated with those scales. A subsidiary Slide Rule this page describes a software package that let's you enter an expression and will tell you how that expression can be evaluated with a slide rule. If you are looking for that software go Slide Rule. They show the two sides of a particular slide rule in my collection. It's made of plastic, and has Slide Rule scales Slide Rule 11 cursor marks. Slide Rule rule is about You can click on the pictures and see an enlarged image, but that doesn't come close to holding the real thing in Slide Rule hands. It feels heavy and solid. The slide and cursor move with silky smoothness and yet they stay in place wherever you let go of them. The lettering is crisp and detailed, and pristine! No space is wasted, but Slide Rule information is not crowded either. Every scale has a purpose. German made slide rules of that time the late s usually come with an accessory plastic ruler. This particular slide rule has a ruler not shown that lists common formulas and physical data on one side. Those may be useful for slide rule calculations. However, the other side of that ruler has a detailed list and explanation of common notations in set theory! This is about as useless for slide rule calculations as a list of large mammals. Apparently this slide rule Slide Rule made when the "new math" was Slide Rule its zenith and Faber Castell wanted its share of the action. The Basic Idea It's clear how to add or subtract two lengths using two ordinary rulers. Slide rules do the same thing, add and subtract lengths, but they don't call them lengths. For example, by calling them logarithms, you can multiply and divide numbers. In fact, I don't know of any slide rule that actually let's you add or subtract numbers. In the heyday of slide rules that was considered a trivial task that you did in your head, or on a piece of paper if you had to. The body and the slide are marked with scales. The cursor has a hairline that facilitates accurate positioning of the cursor at a specific point on some scale. There may be other marks on the cursor that are used for specific and special purposes. Basic Multiplication The most basic procedure carried out on a slide rule is the multiplication of two numbers u Slide Rule v using the C and D scales. These two scales are identical. C is on the slide, and D is on the body. Move the hairline over u on the D scale. Move the slide so that its beginning marked by 1 on the C scale, and also called the index of the C scale lines up with the hairline. Move the hairline to the number v on the C scale. Read the result underneath the hairline on the D scale. If the number v projects beyond the end of the slide rule move the end of the slide rule marked with 10 on the Slide Rule scale above u and read the result as before on the D scale underneath the number v on the C Slide Rule. Why does this Slide Rule The C and D scales show a number Slide Rule that equals the exponential of the distance of x from the beginning of the C or D scale. So basically you are adding the logarithms of the numbers Slide Rule and vand the logarithm of the product equals the sum Slide Rule the logarithms. This is the fundamental identity underlying all slide rule calculations, and it is worth stating prominently: It's convenient to think of the logarithm as the common base 10 logarithm, and the Slide Rule of the slide rule as one unit, but you can also think of log meaning the natural logarithm, and the length of the slide rule being log 10 units. The multiplication of two numbers exhibits two important properties of slide rule calculations: The real number line Slide Rule infinite and slide rules have finite length. Hence all scales can only show a part Slide Rule the real number line. On the C and D scales, any number x is shown as a number between 1 and 10, and it is determined only up to a factor that is an integer power of In other words your slide rule does not usually show the location of the decimal point. You are supposed to understand your problem well enough so you can tell where to put it. The slide rule also does not tell you the sign of your result. Compared to a calculator, a slide rule is severely limited in its accuracy. You can enter and read a number typically to two Slide Rule three decimal digits only. Scales All other scales on a slide rule are referenced to the C and D Slide Rule. Following is a list of scales commonly found on slide rules. For each scale we list the name like Cthe function underlying it likeand some explanations or comments. Name function Comments C, D The basic scales. C is on the slide, D Slide Rule the body. A, B A is on the body, B is on the slide. RW May come with subscripts to distinguish andand have a prime attached to Slide Rule location on the body or slide. These scales are labeled R Root or W Slide Rule. The radical symbol may also be used. K This scale usually occurs by itself, rather than as a member of a pair. LL, E or This is one of the scales that show the decimal point. Usually there are several scales, like. L The only Slide Rule on a slide rule that has a constant increment. Usually on the slide. If there was one such scale on the slide and one on the body they could be used for the addition of numbers. SLists the angle for which of. On slide rules, all angles are measured in degrees, and reside in the interval. The scale usually lists both andusing the identity. TSimilar to the S scale. There may be a similar scale of in the interval in which case subscripts may be used to Slide Rule the scales. Slide Rule showing the angle in degrees in the unit circle for an arc of length where is in the interval. For such small arcs, within the accuracy of a slide rule, the angle measured in radiansthe sine, and the tangent are all equal. P for Slide Rule the interval. The Pythagorean Scale. H for in the interval. There may be another scale for in and the two scales may Slide Rule distinguished by subscripts. Sh is the inverse of the hyperbolic sine. Ch is the inverse Slide Rule the hyperbolic cosine. Th is the inverse of the hyperbolic tangent. Table 1: Common Scales. One Variable The power of a slide rule stems from the interplay of the scales and the movements of Slide Rule slide and the cursor. However, even if your slide was lined up with the scales on the body, but otherwise frozen in place, you could use your slide rule as a lookup table for a Slide Rule number of formulas. Some of them are listed in Tables 2 and 3. For example, if you wish to compute the expression move the hairline over on the CF or DF scale, and read the Slide Rule on the W scale. More generally, if you choose a number on a scale corresponding to the function as listed in Table 1and you read the corresponding number on a scale corresponding to the functionthen. Note that is not the number under the hairline on the C scale, unless you choose to start on that scale! As the tables clearly indicate, Slide Rule you move the hairline over any number on any scale at all, and read the number on the same scale right under the hairline, you'll get that very same number back! Two Variables Of course the Slide Rule of possibilities is vastly increased by allowing the slide to move. Scales 1 Slide Rule 3 are on the body, scale 2 is on the slide. PLUS: Select u on scale 1 on the bodyalign it with the index of scale 2 on the slide Slide Rule, move the hairline to v on scale 2, and Slide Rule the result on scale 3 on the bodyunderneath the hairline. For Slide Rule if the scales involved are DCand Dthe result would be the product, uv. MINUS: Select u on scale 1, align it with v on Slide Rule 2 on the slide, move the hairline to the index of Slide Rule 2, and read the Slide Rule on scale 3 on the body, underneath the hairline. For example, if the scales involved are again DCand Dthe result is the quotient. What happens if we use other scales? Assuming a very hypothetical slide rule that has all the scales listed above both on the body and on the slide, these two procedures let Slide Rule evaluate 3, different expressions in 4, different ways. Six examples are given in Table 4. Click here to see a similarly organized pdf file Slide Rule several hundred pages showing all the possibilities. In general, if is the function corresponding to scale 1 again, as listed in Table 1the function corresponding to scale 2, and the function corresponding to scale 3, then the result that you read on scale 3 is. The symbol indicates whether to use the plus or the minus procedure. The first three rows of Table 4 show the most common operations on a slide rule: product, quotient, and power. The last three rows show less common formulas that can be evaluated. Slide Rule first number in that row,indicates the entry Slide Rule the pdf table26 means it is the 26th distinct formula in the table, and 2 means it's the second way to evaluate this particular formula. How to Use a Slide Rule

Before we had calculators we had slide rules. The circular and rectangular slide Slide Rule were invented by an Episcopalian minister and mathematician William Oughtred. A calculating tool, the invention of the slide rule was made possible by John Napier's invention of logarithms, and Edmund Gunter's invention of logarithmic scales, which Slide Rule rules are based upon. Logarithms made it possible to perform multiplications and divisions by addition and subtraction, according to The Museum of HP Calculators. Mathematicians had to look up two logs, add them together and then look for the number whose log was the sum. Edmund Gunter reduced the labor by drawing a number line in which the positions of numbers were proportional to their logs. Slide Rule Oughtred simplified things further with the slide rule by taking the two Gunter's lines and sliding them relative to each other thus eliminating the dividers. William Oughtred made the first slide rule by inscribing logarithms on wood or ivory. Slide Rule the invention of the pocket or handheld calculatorthe slide rule was a popular tool for calculations. The use of slide rules continued until aboutafter which electronic calculators became more popular. Several inventors improved upon William Oughtred's slide rule. Share Slide Rule Email. Mary Bellis. Inventions Expert. Mary Bellis covered inventions and inventors for ThoughtCo for 18 years. She is known for her independent films and documentaries, including one about Alexander Graham Bell. Updated February 16, ThoughtCo uses cookies to provide Slide Rule with a great user experience. By using ThoughtCo, you accept our.