A monochromatic laser passes through a narrow slit

PHYSICS · Single correct · A Level · Physics · Waves · Waves

Problem

A monochromatic laser passes through a narrow slit, and a detector records the intensity as a function of angle. Intensity minima occur at

\theta=\pm1.5^{\circ}

\pm3.0^{\circ}

, and

\pm4.5^{\circ}

. Which assignment of integer order

m

to these three distinct minima is most consistent with the single-slit diffraction model? (a)

m=0,\,1,\,2

respectively for the minima at

1.5^{\circ}

3.0^{\circ}

, and

4.5^{\circ}

. (b)

m=1,\,3,\,5

respectively for the minima at

1.5^{\circ}

3.0^{\circ}

, and

4.5^{\circ}

. (c)

m=1,\,2,\,3

respectively for the minima at

1.5^{\circ}

3.0^{\circ}

, and

4.5^{\circ}

. (d)

m=2,\,4,\,6

respectively for the minima at

1.5^{\circ}

3.0^{\circ}

, and

4.5^{\circ}