Here’s the answer to the question I asked in the last post: There is no place on Earth where the sun will not shine on the north side of a house.
It’s possible to answer the question with a little fairly common knowledge and some observation. The knowledge you need is that close to the poles in the summer, the sun does not set but instead goes all the way around the horizon, South, East, North and
West. The observation you need is to notice that in the northern hemisphere summer, the sun rises north of East and sets north of West. That means, of course, that the sun shines on the north side of a house in the morning and in the evening. Given that, it seems reasonable to me that you might assume that since the sun shines for part of the day on the north face of a house in the midlatitudes, where most of us live, and for part of the day at the North Pole, there probably isn’t anywhere in between those where the sun doesn’t shine on the north face of a house at some time in the day. And if you assumed that, you would be right.
You can demonstrate it mathematically, but there really isn’t any reason to do it.
Remember, I said it was a trick question.
Most of the information I gave was true but misleading. I mentioned that the sun stays below the horizon all day long for some winter days north of the Arctic Circle. And I mentioned that the noon-day sun is north of the zenith when you’re in the northern tropics. I didn’t mention that the sun never sets on some summer days north of the Arctic Circle, and t didn’t say that the sun has to shine on the north face at noon, only that it must never shine on the north face of a house.
Here’s another trick question.
If you look at your image in a mirror and extend your right hand towards the mirror, the image in the mirror seems to extend its left hand towards you. But if you extend your hand up, the image does the same. So, why does a mirror reverse left and right, but not up and down?
I wish you wouldn’t do that…not at THIS time of the morning. I’m just a half a cup into the day and now I have a headache.
Well that was a good trick. Like all good puzzles it’s obvious after the shaming is over!
Your demonstration of this that works for me is one I can see from here – as summer progresses, the sun rises further and further to the north of east, and sets further north of west. Taken northward to the extreme you can see how it the sun would eventually traverse the entire circle.
Gin — I won’t do much of this. I’m almost out of trick questions … almost, but not quite.
Wayne — The mirror question is also a trick. This one has been around for a long time.
I’m not even sure anyone would wonder why up and down would be reversed – the mirror reflects what it sees. So I suppose it has to do with virtual rays and such, but I was never good at optics.
By the way, there are “true mirrors” constructed so that they do a double reflection, giving a reversed (left and right only!) image, thereby allowing you to see yourself as others see you. I’ve heard that people have changed the parts of hair on their head based on seeing themselves as they really are.
I’m not very good with trick questions particularly ones that require visualizations and math. I have to take out paper and pens, draw pictures, use math, and think. Ugh! I just tried the mirror image of the mirror image. What a relief that it wasn’t halloween scary!