Popular in Course
Popular in Mathematics (M)
This 3 page Class Notes was uploaded by Mrs. Haley Hartmann on Monday October 5, 2015. The Class Notes belongs to MTH553 at Central Michigan University taught by Staff in Fall. Since its upload, it has received 24 views. For similar materials see /class/218899/mth553-central-michigan-university in Mathematics (M) at Central Michigan University.
Reviews for HstElemMthK
Report this Material
What is Karma?
Karma is the currency of StudySoup.
Date Created: 10/05/15
The Slide Rule A slide rule is a mechanical analog device consisting of two nely divided scales with a movable inner one and a sliding window called a curser The slide rule is used primarily for multiplication and division but can also be used for functions such as trigonometric functions square and cube roots exponential functions and logarithms It does not do well with addition or subtraction Before calculators this was the most commonly used instrument for doing mathematical computations The use of the slide rule grew through the 1950s and 1960s even as digital computing devices were being developed In the early to mid 1970s however the electronic scientif1c calculator was introduced and the slide rule quickly became obsolete The slide rule uses logarithmic scales to allow for quick computations It builds on the fact that 10gXy 10gX 10gy 10gXy 10gX 710gy In general mathematical calculations are performed by aligning a mark on the sliding central strip with a mark on one of the fixed strips and then observing the relative positions of other marks on the strips The user needs to determine the location of the decimal point in the result based on mental estimation History The slide rule was invented around 16201630 shortly after John Napier s publication of the concept of logarithm Edmund Gunter of Oxford developed a calculating device with a single logarithmic scale that could be used for multiplying and dividing William Oughtred in 1632 combined two logarithmic scales directly opposite each other to do calculations The more modern form of the slide rule was created in 1859 by French artillery lieutenant Amedee Mannheim It was around that time that engineering became a professional field and this helped spread the use of a slide rule across Europe They did not become common in the US until 1881 when Edwin Thacher introduced the cylindrical rule During the 19Lh century Germany had a steel slide rule about 2 meters long that was used at one astronomical observatory It had a microscope attached giving it 6 decimal places of accurac Throughout the 1950s and 1960s the slide rule became the symbol of the engineer s profession in the same way that a stethoscope symbolized the medical profession Traditionally slide rules were made out of hard wood such as mahogany or boxwood with cursers made out of glass and metal Later they were made out of plastic or aluminum and the cursers were made of acrylics Advantages A slide rule moderates the fallacy of false precision A slide rule requires a continual estimation of order of magnitude since one needs to determine the placement of the decimal point hisherself When performing a sequence of multiplication or division by the same number you simply need to glance at the slide rule to get multiple answers A slide rule can be easily replicated without electrical knowledge Classroom sets can be made out of paper or cardboard They are highly standardized so you don t have to releam when you switch to a new one At the time that they were popular they were much less expensive than current calculators Disadvantages Errors may arise from mechanical imprecision Calculations are limited in precision They are more like estimations than calculations 39 Depending on the calculation calculators will sometimes be quicker Review of Logaritth log1 0 log10 1 log100 2 log1000 3 etc The log of any number between 1 and 10 is between 0 and 1 The log of any number between 10 and 100 is between 1 and 2 The log of any number between 100 and 1000 is between 2 and 3 Etc Also note log3 477121 log30 1477121 log300 2477121 Guess what log3000 is Also note that 3000 300 X 10 so log3000 log300 log10 Problems 34X51 237 X 72 237 X 29 721 X 87 837 6979 7592