Can Light Pressure Energy Influence Momentum and the Doppler Effect?

AI Thread Summary
Light, despite having no mass, possesses momentum and can exert pressure when reflected. When light reflects off a moving object, it loses energy if the object is moving away and gains energy if the object is moving toward it, with the Doppler effect playing a crucial role in this energy exchange. The discussion highlights the relationship between light pressure, momentum, and the Doppler effect, clarifying that energy changes occur based on the relative motion of the light and the object. Understanding these principles is essential for grasping how light interacts with moving bodies. The interplay of light, momentum, and energy is a fundamental concept in physics.
Daniel Petka
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Light has no mass. It has a momentum, though. That means it can potentially push things when reflected and therefore lose energy due to the doppler effect, right? Does it mean that it gains energy when it slows down things and doesn't lose any energy if it doesn't push anything? If the whole thing has nothing to do with the doppler effect, then please tell me how it works.

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You are correct. Light loses energy when it is reflected from an object that is moving away and gains energy when it is reflected from an object that is moving toward the light. In both cases, the Doppler effect is responsible.
 
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