Quick question..... What do we use for reaction time?
and
Say we have a pendulum..... In two readings if found the time taken for 20 osc was 50.45 and 55.56 seconds.
what is the time taken for 1 period and what is the uncertainty. 
Reaction time :
0.2sYou should use the columns in your table to insert t
1, t
2, mean time<t> and then periodic time(T)
N=20
t1= 50.45s t2= 55.56s
Hence mean time <t>= (50.45 + 55.56)/2 =
53.01sPeriodic time = 53.01/20 =
2.651sUncertainty is the reaction time, since the stopwatch used measured values upto 4sf which makes an uncertainty of 0.01 which is negligible when compared to 0.2s of reaction time.
% uncertainty = 0.2/2.651 * 100 =
7.5%Hope it helps
