Why do we have a leap year? We have a leap year because the calendar year doesn’t exactly match the solar year. Earth orbits the sun at an average distance of 149,600,000 km. We travel around the sun in a clockwise direction and we travel about 940 million km with every orbit. One orbit of […]
#877 Why do we have a leap year? Read More »
Why does a golf ball have dimples? They make the ball go further. Golf balls didn’t always have dimples. The game was invented in Scotland in the 15th century, but it could be connected to a game called paganica that was played in Rome. It could also be connected to a Chinese game called chui.
#876 Why does a golf ball have dimples? Read More »
What happened to Detroit? Detroit declared bankruptcy in 2013, with debts of $18 billion. Detroit was the fourth largest city in the United States at one point and so large that nobody could ever have imagined that it would fail. Indigenous people have lived in the area for thousands of years and the first Europeans
#875 What happened to Detroit? Read More »
Where does cork come from? Cork comes from the bark of the cork oak tree. The primary use of cork is to stop up wine bottles. About 20 billion bottles of wine are produced a year and about 80% of those bottles have cork stoppers in them. That is a huge amount of cork and
#874 Where does cork come from? Read More »
Why does a pulley make weights easier to lift? They increase mechanical advantage. The pulley is an invaluable invention that has helped humankind immeasurably. Without it, many of the things we take for granted, such as elevators, wouldn’t work. The pulley was possibly invented in Ancient Egypt in roughly 2600 BC. A pulley has been
#870 Why does a pulley make weights easier to lift? Read More »
Can you live without a spleen? The spleen serves many functions, but you can live without it. Having it removed will affect your life, though. Your spleen is just inside your left rib cage, above your stomach. It is about 12 cm long and weighs approximately 70 g, about the size of an avocado. So,
#869 Can you live without a spleen? Read More »
How does an ejection seat work? In the simplest sense, they remove the canopy to the plane and then launch the pilot on their seat into the sky before a parachute deploys. Ejection seats are a lot more advanced than they were when they were first invented. The first ejection seats were first used during
#868 How does an ejection seat work? Read More »
What is the upper limit of a speaker? The loudest speaker ever made produced 165 decibels. No speaker could ever go above 194 dB, because sound has an upper limit, just like temperature. There are a few considerations when trying to make a speaker that can produce very loud sounds. The first is that the
#867 What is the upper limit of a speaker? Read More »
Nils Bohlin invented the three-point seat belt in 1959. There is no way of working out how many people his invention has saved, but it must be over a million, at least. The US National Highway Traffic Safety Administration thinks that the three-point seatbelt saves about 15,000 lives a year in the US alone. Bohlin
#866 Nils Bohlin – inventor of the three-point seatbelt Read More »
What is a karat? It is a way to measure the purity of gold. (In the UK, karat is spelled as carat – more on that later). However, a carat is a unit of mass that is 200 mg. It is used for measuring gemstones and pearls. Both Karats and carats are not used to
#862 What is a karat? Read More »
