Physics for the curious, not just the experts.
Start wherever you are — your first week of physics class or deep into AP prep. You'll find topics explained clearly, actual research broken down without the jargon, and next steps if you're wondering where physics could actually take you.
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Pick a topic and a level, and start reading. No prerequisites required.
Research
Actual research papers explained in plain English, plus what’s new in physics this week.
Get Involved
Scholarships, internships, and competitions worth knowing about, sorted so the closest deadlines show up first.
Careers
What physics careers actually look like, from people who are living them.
Physics is everywhere
Atoms are mostly empty space
The nucleus is about 100,000 times smaller than the atom around it.
White light is every color
A prism doesn’t add color. It just spreads out what was already there.
Magnets have invisible fields
You can’t see them, but you can see what they push around.
The Moon is always falling
It’s falling toward Earth constantly. It just keeps missing.
This week's picks
What Shapes the Fine Details of the Northern Lights? Maybe Bouncing Electrons
A new study suggests that tiny structures in the aurora could form when electrons bounce off waves in the plasma high above Earth.
newsScientists Build a Nuclear Clock That Corrects Its Own Laser
A team in Vienna and Germany kept a clock based on the nucleus of an atom running on its own for more than 24 hours.
Physics in Everyday Life
Why You Get Shocked by a Doorknob
Shuffle across a carpet in socks and then reach for a metal doorknob, and zap. The shock comes from static electricity. Rubbing your feet on the carpet moves electrons between the carpet and you, so your body ends up with extra charge. Because like charges repel, that charge spreads out over your body, and it has nowhere to go until you touch something that conducts.
When your finger gets close to the metal doorknob, the electric field in the tiny gap becomes so strong that it pulls charges across, and the air briefly breaks down into a spark. That’s the zap you feel and sometimes see. It happens a lot more in dry winter air, because moist air lets the extra charge leak away before it builds up.