Here's an exam question that confused me:
Time for bar to swing through 10 oscillations as measured by a stop clock = 15.7 s
Determine the percentage uncertainty in the time t suggested by the precision of the recorded data.
My answer - 0.05/15.7 x 100 = 0.3%
Mark scheme - 0.1/15.7 x 100 = 0.64%
I thought that the absolute uncertainty would be +-0.05 secs, secondly I've read that uncertainties should always be given to 1 significant figure. Could someone clarify this for me?