Changes

# Find out how much uranium is in the specimen now.

# Find out how much uranium is in the specimen now.

# Calculate how much uranium has turned into lead.

# Calculate how much uranium has turned into lead.

# Calculate how long it would take that much uranium to turn into lead, given the measured rate.

# Calculate how long it would take that much uranium to turn into lead, given the measured rate.  Calculations involve the well-established function for exponential decay: <math>F</math>_{<math>t</math>}<math>=e</math>^{<math>-kt</math>}.

== Key assumptions ==

== Key assumptions ==

The process of decay is as follows.  Atoms consist of a heavy central core called the [[nucleus]] surrounded by clouds of lightweight particles (electrons), called [[electron shell]]s. The energy locked in the nucleus is enormous, but cannot be released easily. The phenomenon we know as heat is simply the jiggling around of atoms and their components, so in principle a high enough temperature could cause the components of the core to break out. However, the temperature required to do this is in in the millions of degrees, so this cannot be achieved by any natural process that we know about. The second way that a nucleus could be disrupted is by particles striking it. However, the nucleus has a strong positive charge and the electron shells have a strong negative charge. Any incoming negative charge would be deflected by the electron shell and any positive charge that penetrated the electron shells would be deflected by the positive charge of the nucleus itself.

The process of decay is as follows.  Atoms consist of a heavy central core called the [[nucleus]] surrounded by clouds of lightweight particles (electrons), called [[electron shell]]s. The energy locked in the nucleus is enormous, but cannot be released easily. The phenomenon we know as heat is simply the jiggling around of atoms and their components, so in principle a high enough temperature could cause the components of the core to break out. However, the temperature required to do this is in in the millions of degrees, so this cannot be achieved by any natural process that we know about. The second way that a nucleus could be disrupted is by particles striking it. However, the nucleus has a strong positive charge and the electron shells have a strong negative charge. Any incoming negative charge would be deflected by the electron shell and any positive charge that penetrated the electron shells would be deflected by the positive charge of the nucleus itself.

=== Outside influences ===

=== Outside influences ===