A single slit of width 2.0μm is illuminated by monochromatic light of wavelength 600nm, and the diffraction pattern is observed on a distant screen.
(i) Using the exact condition for the first diffraction minimum, calculate the angle (in degrees) between the central maximum and the first minimum.
(ii) Obtain the angle using the small-angle approximation.
(iii) Determine the percentage error introduced by the approximation.
(iv) Based on your calculations, state whether the small-angle approximation is acceptable for this experiment and justify your answer.