Tony Towner
Well-known member
- Joined
- Feb 18, 2010
- Messages
- 38,454
- Reaction score
- 24,790
Gain a new fact one day and lose it the next
Magnification through glass, plastic, water droplets? Does, e.g., paper ignite at a lower temperature?So I've done some reading, and it seems fires can sometimes just start on their own. But I don't understand how the sun alone can take something up to the ignition point of dry wood / grass which is about 300 degrees. Can anyone explain?
So I've done some reading, and it seems fires can sometimes just start on their own. But I don't understand how the sun alone can take something up to the ignition point of dry wood / grass which is about 300 degrees. Can anyone explain?
Magnification through glass, plastic, water droplets?
Maybe like grass and dead matter acting like a compost pile where it can get really hot underneath?
You have me sat here wondering where the spark comes from though
Reflection off a concave surface can give the same concentration of energy as through a lens.Magnification through glass, plastic, water droplets? Does, e.g., paper ignite at a lower temperature?
Where do you find a concave surface in nature though?Reflection off a concave surface can give the same concentration of energy as through a lens.
Where do you find a concave surface in nature though?
I can honestly say that I can't recall ever seeing a surface which looked concave enough and shiny enough to be a fire hazard.You've never seen a natural concave surface?
wood dust is a big fire risk. considered potentially explosive in wood stores. whilst presumably far less concentrated in the open air but there must be small particles that might alight in hot conditions? friction against other small particles?Maybe like grass and dead matter acting like a compost pile where it can get really hot underneath?
You have me sat here wondering where the spark comes from though
I can honestly say that I can't recall ever seeing a surface which looked concave enough and shiny enough to be a fire hazard.
David Cameron’s chin.I can honestly say that I can't recall ever seeing a surface which looked concave enough and shiny enough to be a fire hazard.
To be honest I’m surprised at that. Charlwood is about 15 miles south of here next to Gatwick and looking at the maps the predictions are for the hottest spots to be further north, probably much closer to a lot of you guys.The record has already gone.
39.1 has been recorded in Surrey today.
Obviously following Epsom(Cambridge) Wolf aroundThe record has already gone.
39.1 has been recorded in Surrey today.
You don't need a spark...Maybe like grass and dead matter acting like a compost pile where it can get really hot underneath?
You have me sat here wondering where the spark comes from though
It's going to have to be fairly shiny and fairly concentrated to start a fire. I watch loads of shite on YouTube, what used to be discovery etc and never heard of this. Is there anything out there where the cause has been identified as something like this?Things don't have to be shiny to reflect, it doesn't need to be a perfect curve to reflect things back to a more concentrated area.
Your thinking is far too influenced by human invention, all of the man made objects you're thinking of are refinements of things that exist in nature to maximise the effect they have and thus be consistently useful to us.
Obviously following Epsom(Cambridge) Wolf around