PHYSICS · Multi-part · A Level · Physics · Measurements and their errors · Measurements and their errors
Problem
In an experiment on a steel wire, a photograph taken at one instant shows two consecutive crests at positions x = 12.0 cm and x = 42.0 cm (uncertainty in each position ±0.02 cm). A separate timing shows that the crest initially at x = 12.0 cm reaches x = 52.0 cm in (0.80 ± 0.01) ms.
(a) Determine the wavelength.
(b) Calculate the speed of the wave.
(c) Compute the percentage uncertainty in the speed, taking all stated uncertainties into account.
(d) The accepted speed for waves in the wire is 500 m s⁻¹. Comment whether your experimental value agrees with the accepted value within the uncertainty limits.