Recent content by no_audio

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    What does it mean for an object to absorb or reflect light?

    Is it fair to say the following? "When light shines on an object, say a green leaf, it excites electrons on the atoms of the leaf to go to higher energy levels. As the electrons fall back to lower energy levels, the atoms of the leaf emit photons with the energy E = hv where h is Planck's...
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    What (physically) to do in a falling elevator?

    I understand that surviving an elevator fall is unlikely, but physically speaking, what is one supposed to do to maximize one's chances of survival? Why?
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    The Concept of Work in Electric Fields

    I wish I could tell you how relieved I am to finally understand something that has been plaguing me for quite some time. I almost teared when I read the post. Thank you so, so much.
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    The Concept of Work in Electric Fields

    What is the difference between positive work and negative work? Because the definition of work is the dot product of the force and displacement vectors, I can see that work is negative when the force acts in the "opposite" direction of the displacement. Also, I see that W = -(delta)PE. I ask...
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