What does "rpm" stand for when describing how fast something spins?
AnswerRevolutions per minute
Rpm counts how many full turns something makes in one minute.
Science · Facts & stats
Top facts & stats
7 fact-checked facts about spinning tops, each with the reason behind it. 5 more are in today's round and join this page after it closes.
The basics
A top will usually spin longer on which surface?
AnswerA smooth, hard surface
Smooth, hard surfaces create less friction at the tip, so less spin is lost each second.
Going deeper
How is a traditional whip top kept spinning?
AnswerBy lashing it with a small whip or cord
Whip tops are set spinning and then kept going with repeated flicks of a short whip or cord.
How does a humming top make its sound?
AnswerAir moving through openings in its hollow body
Humming tops are hollow with slots or holes, and spinning drives air through them to create a hum or whistle.
Why do many tops have a wide, heavy rim?
AnswerMore mass at the rim helps them keep spinning longer
Mass far from the axis gives a larger moment of inertia, so the top stores more spin and resists slowing.
Expert level
What surprising move does a tippe top make while spinning?
AnswerIt flips over and spins on its stem
A tippe top starts on its round body, then friction makes it invert and spin on its short stem.
What is the traditional Japanese word for a spinning top?
AnswerKoma
In Japan tops are called koma; kendama is a cup-and-ball toy and daruma is a round wishing doll.
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