Calculating % Error on Atwood's Machine Lab

[blimkie]

hi all
im doing a lab on the atwoods machine basically i ahve calulated gravity as eqaul to 7.09 m/s^2 so i am way off because tis really 9.81. its because of human error when i was using the stop watch.
i can't rember the formula for figuring out the perecentage of error even tho its really simple lol
its sumthing like 9.81 - 7. 09 then u multply or divive to get ur percentage
haha thanks

 

[ranger]

http://www2.volstate.edu/tfarris/PHYS2110-2120/experimental_error_files/image002.gif

Dont forget to take the absolute value of the numerator.

 

[blimkie]

thanks a lot