Radioactive dating (Uranium)

Uranium is a radioactive element so it decays into an isotope of another element at a fixed rate. Uranium 238 is an isotope of uranium and it has a half life time of about 4.5 billion years.In the case of Uranium ,it finally forms lead 206.Scientists know the rate of transformation of uranium 238 to lead 206,they can determine the age of the rock containing lead 206.
Scientists calculate radioactive dating of rocks by taking the ratio of uranium 238 to lead 206.

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