My Math Forum Calculating area in circle question..

 Geometry Geometry Math Forum

 May 5th, 2015, 12:12 PM #1 Newbie   Joined: Dec 2014 From: uk Posts: 10 Thanks: 0 Calculating area in circle question.. Ok... Here's my question, when calculating an area of a circle im getting totally different sizes by using different length types. Eg. A circle wih a radius of 400mm and an angle of 0.8 rad is showing up totally different results to a circle with a radius of 0.4m and an angle f 0.8 rad... After working it out and converting the results they differ. What am I missing here.
 May 5th, 2015, 12:23 PM #2 Math Team     Joined: Jul 2011 From: Texas Posts: 2,949 Thanks: 1555 $\displaystyle A = \frac{\theta}{2} r^2$ $\displaystyle A = (0.4)(400 \, mm)^2 = 64000 \, mm^2$ $\displaystyle A = (0.4)(0.4 \, m)^2 = 0.064 \, m^2$ note ... $\displaystyle 1 \, m^2 = 10^6 \, mm^2$ so ... $\displaystyle 0.064 \, m^2 \times 10^6 \, mm^2/m^2 = 64000 \, mm^2$ same same.
 May 5th, 2015, 12:42 PM #3 Newbie   Joined: Dec 2014 From: uk Posts: 10 Thanks: 0 So it is... :/ Had bit of a dull moment.

 Tags area, calculating, circle, question

 Thread Tools Display Modes Linear Mode

 Similar Threads Thread Thread Starter Forum Replies Last Post Denis Geometry 5 May 2nd, 2015 12:00 PM joelphilippage Geometry 3 September 17th, 2014 03:53 PM yeoky Algebra 4 May 3rd, 2014 01:06 AM Mercury Algebra 6 February 19th, 2013 08:58 PM gus Algebra 1 April 17th, 2011 04:25 PM

 Contact - Home - Forums - Cryptocurrency Forum - Top