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Science and Nature
Physics Girl

Is energy always conserved?

Join host Dianna Cowern as she puts her MIT physics degree to the test. With experiments, demonstrations, and cool new discoveries, Physics Girl sheds new light on the fun, adventurous side of physical science.

Is energy always conserved?

Season 1 Episode 19 | 5m 16s | CC

When light passes through the universe and is redshifted by the expansion of space itself, how is energy conserved? The stretched light has a longer wavelength and therefore a lower energy. Is energy conserved? If so, where does it go?

Physics Girl

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