Speed of Light Using Purchase Receipts

There are lots of videos showing how to use a microwave oven and some substance that melts, like chocolate to measure the speed of light. My variation isn't edible, but it is cheap, makes use of hings that would otherwise go in the trash and it is accurate.

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    2 Discussions


    6 years ago on Introduction

    To avoid confusion about light vs. microwaves, I should have added that the only difference between visible light and invisible microwaves is wavelenght. All electromagnetic radiation travels at the same speed under the same conditions.

    Also, the frequency of your microwave oven may be on a sticker on the back or bottom of the unit instead of inside.


    6 years ago on Introduction

    Thank you for sharing your genius! Wow, that was fascinating! And inventive!