You know how sunshine can bounce off glass windows into our eyes, making it hard to see? Well, a skyscraper in London, England has an even bigger problem: the light reflecting off it is so strong that it’s hot enough to melt things. Car doors and mirrors have melted, store carpets have caught on fire, and even stone steps have cracked in the heat. This crazy stuff is happening because the side of the building is curved, so the windows focus all the light into one small point, making a really, really strong beam (the same thing happens when you look at the inside of a spoon and see yourself upside down: the light bouncing off is crossing itself at a point in the middle, called the “focal point”). People aren’t sure how to fix the problem other than rebuilding that whole side of the skyscraper. For now, if you ever drive down Fenchurch Street, watch where you park your car.
Wee ones: If you park your car at 1:00 and it starts melting an hour later, at what time is that?
Little kids: If the building melts 2 car doors, 2 tires and a side mirror, how many car parts did it melt? Bonus: If it takes 40 minutes for the building to start melting your car and you parked it 35 minutes ago, how many minutes do you have left before your car starts melting?
Big kids: If a new car parks in the danger spot every 2 hours, how many cars are in danger over a 12-hour period of sunshine? Bonus: What if a new car parks every hour and a half – now how many cars in 12 hours?
The sky’s the limit: Suppose you wanted to build your own car-melting building with 500 windows on that side. If the building can be at most 100 floors tall, how many building configurations (number of floors and number of windows across) can you build?
Wee ones: At 2:00.
Little kids: 5 parts. Bonus: Only 5 minutes!
Big kids: 6 cars. Bonus: 8 cars.
The sky’s the limit: There are 9 possibilities: 1 floor by 500 windows wide; 2 floors by 250 windows wide; 4 by 125; 5 by 100; 10 by 50; 20 floors by 25 wide; 25 floors by 20 wide; 50 by 10; and 100 floors by 5 windows wide.