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WikiCards · Card list · Science cards · Central force
Common card · Science
Central force, a Common card
In classical mechanics, a central force on an object is a force that is directed towards or away from a point called center of force.
- Rarity
- Common
- Domain
- Science
- ATK
- 44
- DEF
- 14
- Power
- 58
- Wikipedia reads a year
- 8,200
Power 58 (ATK + DEF): stronger than 5 % of WikiCards cards.
Central force quiz: 3 questions
Three questions on the Central force card, the way WikiCards duels ask them. Pick an answer, the facts are just below.
Find the missing word
Not all central force fields are ______ or spherically symmetric.
Answer
conservative. Not all central force fields are conservative or spherically symmetric. From the Central force article on Wikipedia.
Which of these Wikipedia articles is read the most in a year?
Answer
The Holy Family. The Holy Family 15,000 · Simon Tatham 12,000 · Central force 8,200 · Osmometer 4,700 Wikipedia reads over a year.
In a duel, each round asks a question like these about the opposing card, with 15 seconds to answer.
The facts on the card
The card carries these facts from its Wikipedia article.
- F = F r ^ where F is a force vector, F is a scalar valued force function, r is the position vector, ‖ r ‖ is its length, and r ^ = r / ‖ r ‖ {\textstyle {\hat {\mathbf {r} }}=\mathbf {r} /\|\mathbf {r} \|} is the corresponding unit vector.
- Not all central force fields are conservative or spherically symmetric.
- However, a central force is conservative if and only if it is spherically symmetric or rotationally invariant.
Why it is Common
Rarity in WikiCards follows a year of Wikipedia page views: the most read articles become Epic and Legendary cards. The Central force article was read about 8,200 times in a year. ATK comes from the length of the article and DEF from its quality, so this card hits with 44 and blocks with 14: each hit it takes is cut by 6 %.
How to get Central force
Open packs. Each pack holds five cards drawn from real Wikipedia articles, the rarest last, and the fifth card is always Rare or better. The odds are shown in the game. A free pack arrives every hour and two can wait, and the Coins you win in duels buy more packs.
More Science cards
Cards close in power
The cards just above and just below Central force in the power ranking, all domains together.
- Concert danceCommon · Science · ATK 45 DEF 13
- Dainis KrištopānsCommon · Society · ATK 44 DEF 14
- The Chronology of Ancient Kingdoms AmendedCommon · History · ATK 45 DEF 13
- Kōda RohanCommon · Arts · ATK 43 DEF 15
- Stadio Romeo MentiCommon · Society · ATK 39 DEF 19
- The Star MoneyCommon · Arts · ATK 40 DEF 18
Card lists
- Wikipedia quizNew questions every day
- All cards from A to ZEvery card, by name
- Science cards
- Legendary cards
- Tier listS and A tiers by power (ATK + DEF)
Credits
Text : Wikipedia, Central force (revision), CC BY-SA 4.0. Photo : Svjo, CC BY-SA 4.0, Wikimedia Commons.
