1 Ã Van de Graaff generator 1 Ã electrically-insulating stool Some confetti, or aluminium foil, or foil cake trays. The demonstration. This demonstration involves high voltages, and so it should never be done by anyone with a pacemaker or other internal electrical device, or who thinks they might be pregnant.
Minimum Advance Purchase. Airlines increase prices dramatically 14 days and 7 days before departure, respectively, according to figures analyzed by FareCompare. To avoid these sharp spikes, you should aim to purchase your ticket a minimum of 15 days prior to departure. Air travel experts at FareCompare say that the window for purchasing tickets at the best price is between three months and 14 days in advance.
Notably, it's also bad for your pocketbook to book too far in advance, according to CheapAir. People who booked 210 days before the flight ended up paying an average of $475 for a domestic ticket. There are exceptions and caveats, however. If you're booking for a high-traffic time, like Thanksgiving, it can make sense to book well in advance. The optimal time to buy a flight for Thanksgiving weekend in 2012, for instance, was 96 days in advance.