Medical tech deserves its own section; without it we’d live in a very different world—a less healthy world.

People’s lives keep increasing, which is pretty nice. Think of all the extra ice cream they get to eat. Who’s to thank? Medicine. Thank you, medicine. And thank you, physics, which plays a huge role in bringing us the medical technology that does this health voo-doo. In fact, medical physics is now considered to be a major field of study in its own right.

Machines like MRI scanners were developed with physics in mind. MRI scanners take an image of the inside of our bodies so doctors can figure out what’s wrong with us. And they work on the principles of electricity and magnetism. The human body contains lots of tiny magnets, and an MRI scanner is a gigantic magnet. That gigantic magnet is used to line up all the mini magnets inside our bodies. When the magnet is switched off, the mini magnets go back to normal, but because different tissues inside our bodies take longer to go back to normal than others, this can be used to create a picture of our insides.

There are many more examples where MRI scanners came from. Pace-makers (the closest things we have to bionic hearts at the moment) use the physics of electricity to send signals that make the heart beat at the right time, ventilators use the principles of fluid pressure to breathe for us, heart monitors and EKG machines involve analyzing wave patterns...the list goes on and on.