I think that even 9.8 is too fussy. Unless you are doing a real life engineering problem involving injury or death to people, 10 m/s2 is more than good enough for classroom use.
Bob at PC
________________________________
From: phys-l-bounces@carnot.physics.buffalo.edu on behalf of Larry Smith
Sent: Sat 4/19/2008 9:16 PM
To: Forum for Physics Educators
Subject: [Phys-l] 9.80 vs. 9.81
The value of g at my location is less than 9.80 m/s^2, and Randy Knight
uses 9.80 in his textbook, but NIST says the accepted value for standard
gravity is 9.80665 which rounds to 9.81. Most textbooks use 9.81 when they
want three sig-figs (but not Knight).