Carbon-14 has a half-life of 5,730 years. if scientists discover a mummified cro-magnon specimen, they will first want to determine its age. when examining a sample from the bone remains, the scientists discover the specimen is composed of 25% carbon-14 and 75% nitrogen-14. how old is this specimen?

the specimen has 11460 years old

Explanation:

if the live sample has as initial amount of Yo C14, the dead sample will have 0.25Yo of C14.

the rate of decay of radiactive matter over time is

∴ Y(t) = 0.25Yo;  T = 5730

⇒ 0.25Yo = Yo * e (( - t * Ln2 ) / 5730 )

⇒ 0.25 = e (( - t * Ln2 ) / 5730 )

⇒ Ln(0.25) = ( -  t * Ln2 ) / 5730

⇒ - 7943.466 = - t * Ln2

⇒ 7943.466 / Ln2 = t

⇒ t = 11460 year

explanation:

it can be observed without changing the identity of the object.

it depends on what substance you're talking about as well as many other factors. in quantum mechanics, the observation of particles affects the observers ability to measure certain properties. for example: you can know the velocity of a particle, but you can't know it's position; or you can know it's position, but not it's velocity. it's like trying to find out where a grain of sand is by throwing other grains of sand at it. once you find out where it is, it's been moved. it's also like trying to find an answer to the question of whether or not a tree falling in a forest makes a sound if nobody is there to hear it. paradoxically, the only way to find out is to be there and hear it.