The slide rule

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The Slide Rule

Hackware v2.2 (7 Sept 2016) By: Yeo Kheng Meng ([email protected])

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So what is a slide rule?• The slide rule is a mechanical analog computer. • It is used primarily for multiplication and division, and also for functions

such as roots, logarithms and trigonometry, but is not normally used for addition or subtraction.

• Invented around 1620-1630 Edmund Gunter• Modern slide rule 1859 by French artillery lieutenant Amédée Mannheim

Source: https://en.wikipedia.org/wiki/Slide_rule

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This rule

• Bought by my dad in 1973• Hemmi P261• Made by Hemmi Bamboo Slide Rule Company Ltd

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Features

• Exponents• Pi • Trigonometry• Powers• Log

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How to use for multiplication and division?

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Decline of slide rules (1970s)• Lower costs of electronic calculators

• HP-35 (1972):• 1972: US$395• 2016: US$2274• 2016: SG$3090

• TI-30 (1976):• 1976: US$25• 2016: US$106• 2016: SG$144