I have a little reflective disc. I will bet you $100 that a reflection of a sunbeam off of it will be exactly the same size (i.e. the same intensity, since it’s not getting any bigger) several meters away as it is a few inches away.
Yes you’re 100% right - it’s not a point-source, so it will expand out slightly. I don’t know the math well enough, but I believe if you if you say you do + it works out to about 1% of distance.
“You” are the sun in this scenario.
As you back up, you fill a smaller and smaller fraction of the mirror. The reflection becomes less sun and more space.
I have a little reflective disc. I will bet you $100 that a reflection of a sunbeam off of it will be exactly the same size (i.e. the same intensity, since it’s not getting any bigger) several meters away as it is a few inches away.
Try that in your backyard with a small mirror. You’ll find the sun’s reflection expands by about 1% of the distance.
Ooooh
Yes you’re 100% right - it’s not a point-source, so it will expand out slightly. I don’t know the math well enough, but I believe if you if you say you do + it works out to about 1% of distance.