Waves from two slits are in phase at the slits and travel to a distant screen to produce the second minimum of the interference pattern.The difference in the distance traveled by the wave is:
A)half a wavelength
B)a wavelength
C)three halves of a wavelength
D)two wavelengths
E)three wavelengths

Question

Quizplus · Accepted Answer

The second minimum of the interference pattern occurs when the path difference between the two waves is equal to $3/2$ wavelengths, or three halves of a wavelength. This is because the first minimum occurs at a path difference of $1/2$ wavelength, and each subsequent minimum occurs at half-wavelength increments.

Waves from Two Slits Are in Phase at the Slits