- NCSLv 72 months ago
Ooh, I don't much care for this setup since even if both transmitters are at antinodes, those antinodes could be selected such that the detector never registers anything.
Still, I think the answer they're looking for is B.
At all integer multiples of the wavelength, the detector is at an antinode, so the value of d is a minimum. 48 cm is at an antinode.
¼ wavelength away (1 cm in this case), the wave is at a maximum, and so d is at a maximum. 47 cm is just such a location.