Radioactive dating game phet answers

EDS 1021 Week 6 Interactive Assignment

Radiometric Dating

Objective: Using a simulated practical application, explore the concepts of radioactive decay and the half-life of

radioactive elements, and then apply the concept of radiometric dating to estimate the age of various objects.

Background: Review the topics Half-Life, Radiometric Dating, and Decay Chains in Chapter 12 of The Sciences.

Instructions:

1. PRINT a hard copy of this entire document, so that the experiment instructions may be easily referred to,

and the data tables and questions (on the last three pages) can be completed as a rough draft.

2. Download the Radiometric Dating Game Answer Sheet from the course website. Transfer your data

values and question answers from the completed rough draft to the answer sheet. Be sure to put your

NAME on the answer sheet where indicated. Save your completed answer sheet on your computer.

3. SUBMIT ONLY the completed answer sheet, by uploading your file to the digital drop box for the

assignment.

Introduction to the Simulation

1. After reviewing the background information for this assignment, go to the website for the interactive

simulation “Radioactive Dating Game” at http://phet.colorado.edu/en/simulation/radioactive-dating-game.

Click on DOWNLOAD to run the simulation locally on your computer.

2. Software Requirements: You must have the latest version of Java software (free) loaded on your computer

to run the simulation. If you do not or are not sure if you have the latest version, go to

http://www.java.com/en/download/index.jsp .

3. Explore and experiment on the 4 different “tabs” (areas) of the simulation. While playing around, think about

how the concepts of radioactive decay are being illustrated in the simulation.

Half Life Tab – observe a sample of radioactive atoms decaying - Carbon-14, Uranium-238, or ? (a custom-

made radioactive atom). Clicking on the “add 10” button adds 10 atoms at a time to the “decay area”. There

are a total of 100 atoms in the bucket, so clicking the “add 10” button 10 times will empty the bucket into the

decay area. Observe the pie chart and time graph as atoms decay. You can PAUSE, STEP (buttons at the

bottom of the screen) the simulation in time as atoms are decaying, and RESET the simulation.

Decay Rates Tab – Similar to the half-life tab, but different! Atom choices are carbon-14 and uranium-238.

The bucket has a total of 1000 atoms. Drag the slide bar on the bucket to the right to increase the number

of atoms added to the decay area. Observe the pie chart and time graph as atoms decay. Note that the

graph for the Decay Rates tab provides different information than the graph for the Half Life tab. You can

PAUSE, STEP (buttons at the bottom of the screen) the simulation in time as atoms are decaying, and

RESET the simulation.

Measurement Tab – Use a probe to virtually measure radioactive decay within an object - a tree or a

volcanic rock. The probe can be set to detect either the decay of carbon-14 atoms, or the decay of uranium-

238 atoms. Follow prompts on the screen to run a simulation of a tree growing and dying, or of a volcano

erupting and creating a rock, and then measuring the decay of atoms within each object.

Dating Game Tab – Use a probe to virtually measure the percentage of radioactive atoms remaining within

various objects and, knowing the half-life of radioactive elements being detected, estimate the ages of

objects. The probe can be set to either detect carbon-14, uranium-238, or other “mystery” elements, as