Two slits are apart and are illuminated with light of wavelength

PHYSICS · Subjective · A Level · Physics · Waves · Waves

Problem

Two slits are

0.25\,\text{mm}

apart and are illuminated with light of wavelength

550\,\text{nm}

. The experimenter wants the second-order bright fringe to be absent from the pattern. Calculate the slit width

a

that should be used.