Proper trailer tongue weight improves the vehicle and trailer towing experience by improving performance. Not enough tongue weight or force on the hitch/tow ball causes an increase in trailer sway from side to side, making it difficult to control. Conversely, too much tongue weight or force on the hitch/tow ball could overload the rear tires of the towing vehicle, pushing the rear end of the vehicle around.
The hot chocolate effect, also known as the allassonic effect, is a phenomenon of wave mechanics first documented in 1982 by Frank Crawford, where the pitch heard from tapping a cup of hot liquid rises after the addition of a soluble powder. It was first observed in the making of hot chocolate or instant coffee, but also occurs in other situations such as adding salt to supersaturated hot water or cold beer. Recent research has found many more substances which create the effect, even in initially non-supersaturated liquids.
San Francisco Airport - SFO