- #1
Master J
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If paper ignites at 500 C, can one start a fire with a typical shaving mirror using sun light?
Since the only time a concave mirror has an upright, virtual, magnified image is with the object between the mirror and focus, I estimate a focal length of about 1m.
Now, the sun is at infinity, so all its light is passed thru the focus. This is where I get stuck. How do I relate the magnification of the mirror to the increase in intensity. I could then use Stefan- Boltzmann to get an idea of temperature, but I am stuck here. Any ideas?
Thanks!
Since the only time a concave mirror has an upright, virtual, magnified image is with the object between the mirror and focus, I estimate a focal length of about 1m.
Now, the sun is at infinity, so all its light is passed thru the focus. This is where I get stuck. How do I relate the magnification of the mirror to the increase in intensity. I could then use Stefan- Boltzmann to get an idea of temperature, but I am stuck here. Any ideas?
Thanks!