I was wondering if I could please have some help with the following question:
A student has a diffraction grating that is marked 3.5 × 10^(-3)
lines per m.
(a) Calculate the percentage uncertainty in the number of lines per metre suggested by this
marking.
The answer is: 2.9%
But according to this answer, the absolute uncertainty is 0.1x10^(-3), however I thought it would be 0.05x10^(-3) because if the number of lines was 3.56x10^(-3), it would have been rounded to 3.6x10^(-3). So was wondering why this is the case. Thanks in advance!