Question 27 • Physics in the Universe
Radiocarbon dating measures carbon-14, which decays at a known rate, but too little remains to measure reliably in materials older than about 50,000 years. Therefore, the accurate statement is that radiocarbon dating cannot be used for materials older than that limit. Dendrochronology dates wood, varves are layered lake sediments, and uranium-lead dating is used mainly for rocks and minerals—not organic material.
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