How do you use a slide rule

1
How do you use a slide rule?

• Basic Ideas
• Logarithmic scales log(xy) log(x) log(y)
  and
• log(x / y) log(x) - log(y)
• Operations multiplication, squaring, cubing,
  finding the logarithm, finding the sine, cosine,
  and tangent
• Inverse Operations division, square root, cube
  root, finding an angle
• Accurate to thousandths place

2
How do you use a slide rule?

• How it works
• Interactive slide rule http//www.taswegian.com/S
  RTP/JavaSlide/JavaSlide.html
• Parts slide, stator (2), cursor, hairline,
  indicator
• Scales
• C, D multiplication and division
• A, D square a number, find the square root
• K cubes and cube roots
• S, T sines and tangents
• L gives the logarithm of a number on the D scale

3
How do you use a slide rule?

• History and Development
• John Napier, a Scottish mathematician, physicist
  and astronomer, invented logarithms in 1614.
• Using logarithms
• to multiply 3.8 by 6.61, you look up the
  logarithms of those numbers in a table. There
  you will find 0.58 and 0.82. Add these together
  to get 1.4. Now go back to the table and find
  the number whose log is 1.4 to get a close
  approximation of the answer 25.12.
• 1620 Edmund Gunter marked a ruler with logarithms

4
How do you use a slide rule?

• History and Development
• 1622 William Oughtred, placed to sliding wooden
  logarithmic scales next to each other to create
  the first slide rule
• 1630, one of Oughtreds students, Richard
  Delamain created the circular slide rule and
  received credit for the invention
• Oughtred charged Delamain as the pickpurse of
  another mans wit

5
How do you use a slide rule?

• History and Development
• 1850 Amedee Mannheim added a moveable cursor
• World War II American bombardiers and navigators
  used specialized slide rules

6
How do you use a slide rule?

• Use of a Slipstick
• Pocket slide rules for engineers
• Fashionable tie clips, went to the moon!
• Where does the decimal place really belong?
• Never made it to daily life
• Became obsolete with the invention of the
  electronic calculator and the pocket calculator