Question

the time for 100 vibrations of simple pendulum recorded by a stop watch is 20.7 +_0.1 sec. the uncertanity in the final result is

Answer 1

Is it 0.004 % ???????????

Answer 2

0.1 out of 20 is about 0.5 out of 100. So that's about 0.5 percent. The uncertainty in the period for a single swing or in the frequency would also be about 0.5%