Likewise, the MPPT varies the ratio between the voltage and current delivered to the battery, in order to deliver maximum power. If there is excess voltage available from the PV, then it converts that to additional current to the battery. Furthermore, it is like an automatic transmission.
On the Supreme Court of the United States, Associate Justices Potter Stewart and Anthony Kennedy have been described as swing votes between the two factions of the court. In the United Kingdom, the  Essex man ,  Worcester woman  and  Holby City woman  are examples of personifications of swing voters.
Those were the questions that the four conservative Justices on the Supreme Court and, to an extent, the presumed swing voter, Anthony Kennedy, asked early on in the oral arguments in Obergefell v. Hodges, a case that has the potential to establish a constitutional right to same-sex marriage in all fifty states. Both questions, though, were overtaken by third: What about the children? And, in debating that, at the end of two and a half hours of back and forth, it sounded like marriage equality was headed for a win.