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.
On most airlines, flights open up for sale 331 days in advance. That is the earliest you can book a flight â about 11 months in advance. We found that for about four months from that time, domestic fares tended to stay pretty steady, and pretty high. That makes sense.