Now, gather around kids for the science corner. No, I’m kidding. At least, I’m halfway kidding. There are so many principles of science that are happening all around you— almost constantly, but most people don’t know them or at least don’t know what they’re called and how they work. So, read on and you might find that answer to last night’s “Jeopardy” question (or a test question in your future physics class!).
1. The Doppler Effect
Ever been sitting in your dorm room and hear a police car fly by with their sirens blaring? I’m sure you have. You heard it from far away— the high-pitched squeal as it went right past your window. It gets quieter as it recedes into the distance. That’s called the Doppler Effect. A shift in the frequency of sound waves around the object causes the siren to sound lower in the distance and much higher the closer it is. The principle was discovered by an Austrian mathematician and physicist named Christian Doppler in the mid-1800s.
You may have heard “Doppler radar” when watching the weather. This principle is used in meteorology where they send radio waves out and see how long it takes for the waves to bounce off the rain and return to the source, telling them the distance and the direction of the rain.
2. The Bernoulli Principle
If you’ve ever been on a plane, you’ve experienced the Bernoulli Principle. This principle, discovered by a Swiss physicist Daniel Bernoulli in the 1700s, explains why planes can be “lighter than air.” This law stipulates that pressure of a fluid (liquid or gas) decreases as the speed of the fluid increases. The shape of a plane’s wing creates lower pressure above the wing than beneath it and this pressure difference allows the wing to push upwards and the plane to fly. The faster the wings move, the more lift is created.
This is direct example of the Bernoulli Principle; the faster a plane moves, the higher it can rise in the air.
3. The Coriolis Force
Ever wondered why a hurricane or typhoon turns clockwise? The flow of wind in curved trajectories is due to the Coriolis Force, discovered by French scientist Gustave-Gaspard Coriolis in 1835. As air flows from high to low pressure, the Earth rotating underneath it serves as the rotating frame of reference that causes the wind to move in a circular fashion.
At the equator the Coriolis Force is zero, while in the Northern Hemisphere it turns the wind to the right, and in the Southern Hemisphere it turns it to the left.