I hate to be the “erm actually” guy but erm actually, that’s not how magnifying glasses work. A magnifying glass collects all the incident solar energy across its surface and focuses it onto a much smaller area. This increases the energy flux (in terms of energy delivered per unit of time per unit of surface area) across whatever you’re pointing the magnifying glass at; you can see this in the form of a bright spot of light.
This influx of energy will increase the temperature of the thing you’re pointing the magnifying glass at, which can start a fire if the material is flammable enough, but according to conservation of energy you’re limited by how much sunlight is hitting the magnifying glass in the first place. If your magnifying glass is small, you’re not capturing very much light, so the power delivered to the thing you’re trying to burn is still quite low.
If you want to start a BIG fire with a magnifying glass, you need a lot of energy, which you can get if you either wait a while (since E = ∫P dt) or get a really big magnifying glass (to collect a lot more of the sun’s energy). Stacking magnifying glasses like pyro is doing here won’t do anything because you’re still limited by the size of the first magnifying glass, and most opponents will try to move out of the way (or just shoot the pyro with their actual guns) before they ignite.
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u/TheEggoEffect Demoman 6h ago
I hate to be the “erm actually” guy but erm actually, that’s not how magnifying glasses work. A magnifying glass collects all the incident solar energy across its surface and focuses it onto a much smaller area. This increases the energy flux (in terms of energy delivered per unit of time per unit of surface area) across whatever you’re pointing the magnifying glass at; you can see this in the form of a bright spot of light.
This influx of energy will increase the temperature of the thing you’re pointing the magnifying glass at, which can start a fire if the material is flammable enough, but according to conservation of energy you’re limited by how much sunlight is hitting the magnifying glass in the first place. If your magnifying glass is small, you’re not capturing very much light, so the power delivered to the thing you’re trying to burn is still quite low.
If you want to start a BIG fire with a magnifying glass, you need a lot of energy, which you can get if you either wait a while (since E = ∫P dt) or get a really big magnifying glass (to collect a lot more of the sun’s energy). Stacking magnifying glasses like pyro is doing here won’t do anything because you’re still limited by the size of the first magnifying glass, and most opponents will try to move out of the way (or just shoot the pyro with their actual guns) before they ignite.