 | Guidance Recommended: This simulation is very effective when used in conjunction with a lecture, homework or other teacher designed activity. |
 | Under Construction: This simulation is a preview version, and may have functional or usability bugs. |
 | Classroom Tested: This simulation has been used and tested in the classroom, and on multiple computer platforms. The simulation has been refined based on that experience and on student interviews. |
 | Gold Star Contribution:
This contribution has received a Gold Star
because it is a high quality inquiry-based activity that follows the
PhET design guidelines
(PDF)
and teachers have found it useful. |
 | PhET Designed: This contribution was designed by PhET. |