Ability to discern two separate sounds, created simultaneously: Rosh HaShanah 27a
Above, in an echoing chamber: Rosh HaShanah 27a, 27b-28a
Above, where they came from one person or two separate people: Rosh HaShanah 27a
Above, where the sound is one to which the listener has an emotional connection: Rosh HaShanah 27a
The distance sound travels at night, vs. during the day: Tosafot Beitzah 7b "d'Shamah"
Optics
The Light of a Candle is more effective at night: Pesachim 4a
The light of a Multi-Wick Torch is cast backward, while a single-wick Candle casts light forward: Pesachim 8a
Vision of the horizon, from the sea and on land: Rosh HaShanah 21a
Why Gd constructed Nature so that the Rainbow's bow never arches from the Sun toward Earth: Rosh HaShanah 23b-24a
Miscellaneous
The difference between a vessel's capacity for liquid volume, and for solid volume, as determined by the surface tension's ability to contain the contents: Eruvin 14b
The amount of water which a unit of earth will absorb in a day: Eruvin 88a-b
The difficulty of transporting a large burden, even if the weight is the same as that of a smaller burden: Bava Metzia 80a
