Question

Does Sunlight weigh anything?

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Answer 1

sunlight has no weightless. If by weight you mean mass, then Sun's light definitely has the equivalent of mass. In particular, the sunlight emitted in a day would be equivalent to 3.7 × 10 14 k g .

Answer 2

Sun’s light composed of photons reaching the earth definitely has equivalent mass. That’s the reason the area covered in shadow weighs less than the area being pushed by light. Especially, the sunlight emitted in a day would be around 3.7*1024 kg.  If you collect all the sunlight in a perfect mirror box, the mass of the box would increase by that amount (because of the photon energy). Furthermore, freely streaming mass-less protons are deflected by gravitational fields.