askscience

Title	Upvotes	Mark as read	Favorited	Rating	Add to a list
If I had 100 atoms of a substance with a 10-day half-life, how does the trend continue once I'm 30 days in, where there should be 12.5 atoms left. Does half-life even apply at this level?	1539
Does the 1.9 mile Klystron Gallery have to account for the curvature of the earth during construction?	90
If pi cannot be expressed as a ratio, and we've never been able to measure a perfect circle with perfect accuracy, how exactly do we know a) the value of pi to the nth decimal place and b) that a diameter and circumference of a circle relate according to pi?	79
Does a steel bar resist bending until a certain amount of force is applied, or does all force bend it, however slightly?	63
If water boils in a vacuum, what happens if there is not much space for the water to expand into (e.g. the airless volume inside a container is only twice the size of the volume of water as a liquid)?	24
If it only takes 23 people in a room to have a 50% chance that two of them share a birthday, how many shuffles of a standard card deck does it take to have a 50% chance that two of them are the same (they end in the same order of cards in the deck) ?	21
Are there any studies about how a group reading a text aloud together (e.g. in a church setting) "agree" on a pace and make the words come out at the same time?	20
What is the absolute fastest that sound can travel, and in what medium can it obtain that speed?	20
What are rocks made out of? Does each type of rock have its own molecules (e.g. granite molecules) or are different types of rocks just different arrangements of the same molecule types?	16
How much variation is there in the sun's position in the sky on the same day of the year, from one year to the next?	16

« < > »