The universe, although grand, is an incredibly sensitive place where the smallest of changes can have the biggest of effects. The science of physics seeks to understand the smallest particles in the universe and harness their properties to make miracles happen. Here are five times physics made a modern marvel possible.
Computers
In computers, information is stored in a binary language of 1s and 0s, transmitted through a system of electrical currents and switches. Present by the billions in a single computer, transistors are the devices that interpret the currents’ voltages into binary language. They are the most fundamental part of computers, and they run on semiconductors like silicon and germanium.
However, creating this technology was not possible until a breakthrough in solid state physics enabled scientists to groom naturally-occurring semiconductors with the necessary properties to function in transistors. This grooming process is called doping. It disrupts the naturally very stable crystal structure of semiconductors so that their refined atomic structure functions like a conductor that can be turned on or off, making them the perfect choice to regulate electric current in computers.
Airplanes
Unless you’re a pilot or aspiring aviation aficionado, thrust-to-weight ratio may not be a familiar term when you think of airplane safety. But without it, airplanes couldn’t take of, and without the scientific principle this ratio is based on, airplanes probably wouldn’t exist at all. 129 years before the Wright brothers were born, Bernoulli’s principle was published in the field of fluid dynamics. Bernoulli’s principle demonstrates that if a fluid moves faster, either its pressure or its potential energy will decrease.
Using Bernoulli’s principle, aviation engineers have been able to calculate the optimal wing shape for a plane and set passenger limits to facilitate take-off. Here’s how it works - when a plane takes off, its engines and propulsion system generate a force called thrust that moves the plane. As the plane moves forward, it displaces air that curves over the plane’s wings, moving faster than the air around it and consequently creating a lower pressure area. Meanwhile, the slower-moving air under the plane’s wings builds pressure, pushing upwards. Since the plane only lifts off once it has reached a speed fast enough in relation to its weight, the thrust-to-weight ratio must be carefully balanced.
Space Exploration
It’s no secret among the scientific community that if it weren’t for Isaac Newton, we wouldn’t be exploring space. Every time a rocket or spaceship blasts off, as its fuel and propellant ignite to produce the tremendous force that launches it, you’re watching Newton’s 3rd Law in action.
More obscure, but equally impactful on space exploration, is the Oberth effect. Hermann Oberth, one of the four founders of modern rocketry, discovered this effect in 1927. It shows that engine force is more effective at higher than lower speeds, a rule of thumb astronauts use to manipulate a spacecraft’s velocity while maximizing valuable resources.
There’s little (if anything at all) about space exploration that didn’t originate in physics. From Newton’s 3rd Law to the mind-boggling formulas used in calculating a spacecraft’s orbit and trajectory, space exploration might be the modern marvel most indebted to physicists.
Nuclear Energy
It’s the most powerful and dangerous form of energy the modern world knows. It’s what made the Tsar Bomba a reality, a weapon that, if detonated on Washington D.C., would cause a radius of damage as far as Baltimore—an area of 4679 miles!
This tremendous energy resides in the bonds that hold radioactive atoms like plutonium together. Since radioactive atoms have extra neutrons or protons and are consequently unstable, they can be broken apart or joined together to form more stable particles. When this happens, tremendous energy is released.
Einstein’s 1905 theory of relativity and famous equation of mass (E=mc2) were the first milestone in unlocking nuclear energy because they showed that mass can be converted to energy. Over the next 30 years physics advanced, until the first uranium atoms were split, producing the release of energy from matter that Einstein’s theory had predicted.
Electricity
Electricity is no longer considered a miracle as much as a modern necessity. Nevertheless, it is no more than mysterious, omnipresent particles, whose power physicists have harnessed to serve society. You probably know Benjamin Franklin as electricity’s discoverer and Thomas Edison as the inventor who created the first commercial electric light bulb.
But no less influential was Nikola Tesla’s contribution of alternating current (AC). Before Tesla’s innovation, the only available distribution method of electricity was direct current (DC), which required cumbersome generators at frequent intervals and whose components quickly wore out. Rather than causing the current to flow in a single direction from a generator, Tesla used magnetics to periodically reverse the current’s direction. This modification created an efficient system still used today to transport electricity for long distances.
The next time you watch a space documentary, jet across the country on a plane, turn on a light, or use an electronic device (hello, smartphone), take a moment to appreciate the miraculous technologies that made these innovations possible. And as you consider the miracles around you, don’t try to count how many principles of physics were involved in their creation--that’s a footprint that might be too big for everyday measurements.