Actually, at the same temperature, the ball travels farther at higher humidity. The difference between 85% humidity and 20% humidity at 85 degrees is only about 1.3 yards for a drive that carries 256 yards.
The reason for this is the fact that at higher humidity, there is a greater proportion of water vapor. Water vapor is less dense than the major gases in the atmosphere (Nitrogen, Oxygen) and therefore the air is less dense. Less dense air offers less drag and less lift, the combination which results in slightly more distance.
Thanks for this. As a Chemistry graduate I feel I should have known (but did not).
Further reading for those scientifically inclined:
The density of a gas is proportional to the weight of a single molecule of
that gas.
So you can figure relative density for yourself if you start learning a few
atomic weights:
H=1, N=14, O=16.
Add them up for the molecular weights of pure gases:
H2 = (1+1) = 2, very light
He = (4) = 4, very light
N2 = (14+14 ) = 28, about neutral
O2 = (16+16) = 32, slightly heavy
H2O= (2*1+16) = 18, light (steam)
For mixed gases just take a proportionate average:
e.g.
- Air is 80% N2 + 20% O2 .
- Dry Air mass (0% humidity) = 0.8(28) + 0.2(32) = 29
- Wet Air (100% humidity is approx 3% water vapour, other 97% is N2 & O2 split as approximated previously. 80:20
- 100% humidity air mass = 0.03*18 + (0.97*0.8)*28 + 0.97*0.2*32 = 28.476
Therefore: 100% humidity air is 1.8% lighter than 0% humidity air (at 30C)
Now back to Alviro's swing. Just love it myself.
