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Home Interactives Refraction and Lenses Least Time Principle

Least Time Principle

The Least Time Principle Interactive is based on the classical premise that light always follows the pathway between two locations that takes the least amount of time. This Interactive uses the analogy of a lifeguard moving from the observation platform along sand, across the boundary into water, and through the water to reach a drowning swimmer. Of course, the path of least time is incredibly important. Learners will test several entry points to determine the entry point that results in the path of least time. Once they have done so, angles of incidence and refraction can be measured and analyzed.
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Users are encouraged to open the Interactive and explore. For a more guided experience, The Physics Classroom has prepared an activity for use with this Interactive and encourages teachers to use it with their classes.

Learners and Instructors may also be interested in viewing the accompanying Notes page. Technical information, teaching suggestions, and related resources that complement this Interactive are provided on the Notes page. View Notes.