Today from Bedtime Math: Mirror, Mirror on the Mountain

 Use the snow day to try this fun math challenge with your kids!

The tops of mountains get lots of sunlight, but if you're in a town low down between two mountains, it's hard for the sun to reach you; a lot of the time you're in the shadow of one mountain or another. And if you're really far north (or south) where the sun swings low in the sky, you might not get any direct sunlight at all! Well, a town in Norway solved this problem with mirrors. They built 3 giant mirrors on a nearby mountaintop, and the sun bounces off those mirrors down into the valley. Since the sun moves across the sky all day (because the Earth is turning), the mirrors have to change their angle, too, to keep bouncing the sunlight towards town. It probably won't warm the air very much, but at least people now know when it's daytime.

 Now here's today's math~

Wee ones: How many mirrors do you have in your house? Can you count them?

Little kids: If the sun rises at 8 am and the mirror starts shining that light into town 2 hours later, at what time does the town start getting sunlight? Bonus: If the mirrors can bounce sunshine into town for only 6 hours of the day, what are some of the start and stop times that could have?

Big kids: Each giant mirror has 4 sections. If each section weighs 500 pounds, how much does 1 mirror weigh altogether?  Bonus: Each mirror is 550 square feet in area, which is its width times height. If the mirror were 55 feet tall, what would be the distance around the edge (its "perimeter")?

Answers:

Wee ones: Different for everyone...

Little kids: At 10 am.  Bonus: Lots of choices...9 am to 3 pm, 10 am to 4 pm, noon till 6 pm...and every in-between time, like 11:25 to 5:25!

Big kids: 2,000 pounds.  Bonus: The mirror would be 10 feet wide, so the perimeter would be 2x55 plus 2x10, or 110+20 = 130 feet.