How could I resist?
Jeopardy! category: MAY THE FORCE BE WITH YOU (04-11-2015)
$400 clue: Whether a climber takes a direct route or a scenic one, it takes the same amount of work to overcome gravity on the way to the top of the mountain because gravity is this type of force, a political antonym of “liberal”
The gist: Named for what it does to mechanical energy, not its side in the culture wars. Gravity, along with others like the spring force and the electrostatic force, are conservative because the work done by a particle (or a mountain climber) to overcome it in relocating from one point to another is the same no matter what path is taken.* In the case of gravity, this is relatively simple to visualize – gravity always pulls you downwards, if you don’t go straight up, there’s less gravity to overcome. That’s why it’s easier to walk up a gradual ramp than a steep one… but you’ll need to walk up a lot more of the gradual ramp to get the same change in altitude.
The clue: I’d never heard of a conservative force, but I know what the opposite of liberal is in American politics, so I got this one anyway. While I bet anyone with a high school familiarity with physics would know this without that hint at the end, a $400 clue should really be able to be gotten by anyone, so it wasn’t a bad inclusion.
In Jeopardy!: “Conservative” is in about 150 clues, but “conservative force” is in only four, and this is the only one that’s actually about physics. The others are: Jerry Falwell’s Moral Majority, that became a major conservative force in American politics; the radical conservative John Birch Society, named for a U.S. Army captain who was killed by Communist Chinese forces days after WWII ended; and Sam Johnson, an Air Force pilot and U.S. Representative, ranked in 2011 as the House’s most conservative, who spent seven years as a P.O.W. in Hanoi, Vietnam.
*An equivalent way of looking at this is that the work done on the particle by the force is the same no matter what path the particle takes. Just a matter of perspective.