Assuming the age of the earth to be `10""^(10)` yaers, the perccentage of original amount of `U""^(238)` is still in existance on earth is x/10% (nearly)(`T""_(1//2)ofU""^(238)is 4.5xx10""^(9)`years). Then 'x' is

A rock is found to contain U-238 and Pb-206 in the ratio of 3 : 2. If t""_(1//2) of U-238 is 4.5xx10""^(-9) years. Calculate the age rock?

Find the amount of ""_(92)U^(238) required to produce a-particles of 20 millicurie strength. The half-life of ""_(92)U^(238) is 4.5 xx 10^(9) years.

In a smaple of rock, the ration .^(206)Pb to .^(238)U nulei is found to be 0.5. The age of the rock is (given half-life of U^(238) is 4.5 xx 10^(9) years).

In a smaple of rock, the ration .^(206)Pb to .^(238)U nulei is found to be 0.5. The age of the rock is (given half-life of U^(238) is 4.5 xx 10^(9) years).

The number of U^(238) nuclei in a rock sample equal to the number of Pb^(206) atoms. The half life of U^(238) is 4.5xx10^(9) years. The age of the rock is

The isotope of U^(238) and U^(235) occur in nature in the ratio 140:1 . Assuming that at the time of earth's formation, they were present in equal ratio, make an estimate of the age of earth. The half lives of U^(238) and U^(235) are 4.5xx10^9 years and 7.13xx10^8 years respectively. Given log_(10)140=2.1461 and log_(10)^2=0.3010.

The isotope of U^(238) and U^(235) occur in nature in the ratio 140:1 . Assuming that at the time of earth's formation, they were present in equal ratio, make an estimate of the age of earth. The half lives of U^(238) and U^(235) are 4.5xx10^9 years and 7.13xx10^8 years respectively. Given log_(10)140=2.1461 and log_(10)2=0.3010.

The isotope of U^(238) and U^(235) occur in nature in the ratio 140:1 . Assuming that at the time of earth's formation, they were present in equal ratio, make an estimate of the age of earth. The half lives of U^(238) and U^(235) are 4.5xx10^9 years and 7.13xx10^8 years respectively. Given log_(10)140=2.1461 and log_(10)2=0.3010.

In an ore containing Uranium, the ratio of U^(238) to Pb^(206 nuceli is 3 . Calculate the age of the ore, assuming that alll the lead present in the ore is the final stable, product of U^(238) . Take the half-like of U^(238) to be 4.5 xx 10^(9) years. In (4//3) = 0.288 .