Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Using log tables

  1. Sep 8, 2011 #1
    how to use a log table..and how to find the value of log 1.6 or log 5.62.
    or any other example.
     
  2. jcsd
  3. Sep 8, 2011 #2

    symbolipoint

    User Avatar
    Homework Helper
    Education Advisor
    Gold Member

    Your Algebra book should have a section, either in the chapter section or in the back of the book, for Computations with Common Logarithms, which gives instructions.

    For your second example, log base 10 of 5.62, find under the lefthand column of the table, under "x", the value of 5.6. Look over to the right hand side under the column, "2", which in your example is your digit 2 in the hundredths place. You find these cross the value in the table, 0.7497. That was the Mantissa. If you had a number to find log of which was less than 1.0 or greater than 10.0, then you would need to use scientific notation for your given number, and the exponent of your power of 10 would be arithmetically ADDED to the mantissa. That power of ten is called the Characteristic.

    log105.62 = 0.7497
     
    Last edited: Sep 8, 2011
  4. Sep 9, 2011 #3

    HallsofIvy

    User Avatar
    Staff Emeritus
    Science Advisor

    Calculators are so common and so easy to use that most texts no longer have log tables or even mention using log tables.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook