#69 How does a gyroscope work?
I learned this today. Gyroscopes work because of the conservation of angular momentum. A gyroscope is useful to us when it is […]
#68 What is the Drake equation?
I learned this today. The Drake equation is a way of trying to guess how many intelligent, communicating extraterrestrial civilizations there might […]
#67 Why do we use a QWERTY keyboard?
I learned this today. The QWERTY keyboard was invented because it made it faster for Morse code typists to type. A common […]
#66 How much time does the Panama Canal save a ship?
I learned this today. The Panama Canal has reduced the journey from the Atlantic Ocean to the Pacific Ocean by 8,000 nautical […]
#65 How can bats sleep hanging upside down?
I learned this today. Bats can sleep hanging upside down because they need to use muscles to open their claws but not […]
#64 What is the difference between alternating current (AC) and direct current (DC)?
I learned this today. The difference between AC and DC current is that in DC the charge only flows in one direction […]
#63 Why do we feel pain when we touch cold or hot things?
I learned this today. We feel pain when we touch something very cold or very hot because of thermoreceptors in our skin […]
#62 Why are zippers called zippers?
I learned this today. Zippers weren’t called zippers until about 30 years after they had been invented and they got their name […]
#61 How do antlers grow?
I learned this today. Antlers are made of bone and can grow up to 1 inch (2.5cm) a day. Antlers are grown […]
#60 Why do birds migrate?
I learned this today. Birds migrate because of declining food sources and not because of the temperature drop over winter. Birds migrate […]