Physical science is the study of the physical world around you. Learn about everything from electricity to magnetism in this section.
The decibel scale measures sound based on human hearing, which makes it one of the most unusual scientific measurements. How are decibel calculated and what do they tell us about sound?
I recently used chlorine bleach to clean the siding on my house, and I was amazed at how well it worked! What is bleach? How does it remove stains? Is the chlorine in bleach the same as the chlorine in drinking water or in swimming pools? Is chlorine safe to use?
I have heard that carbon monoxide is extremely poisonous. Can you explain why?
When I stand at the water's edge and look out over the ocean, how far away is the horizon? Is there an equation to figure it out?
What is dioxin? There's a lot of discussion going on in my town about dioxin and its dangers.
I once saw this device shaped like a light bulb. It had a vertical support inside it, and on that support there were four vanes with four diamonds on the end. One side of the diamond was black and the other was white. I did a little research and found out that it was called a Crookes' radiometer -- how does it work?
I have a thin piece of plastic mounted on the back window of my RV. It magnifies things so I can see better when I'm backing up. How can such a thin piece of plastic magnify things? A regular glass magnifying lens would have to be curved on both sides and much thicker.
Bullets, wires and nails are all measured with unusual measurement systems and units -- and they all show just how interesting measurement systems can be!
Many ads for new clocks advertise their ability to automatically synchronize themselves with the atomic clock in Boulder, Colorado. This atomic clock is more precise because it uses the frequencies of atoms as its resonator.
Chemical formulas provide a concise explanation for reactions. In this article, we explain the formula for the reaction in a smoke detector.
When an airplane flies faster than the speed of sound, you hear a large booming sound. But how can something that seems so simple cause such a boom?
If the idea of being completely knocked out by a cocktail of drugs while doctors operate on you freaks you out, you're not the only one. But that's not what anesthesia is all about it -- and it might scare you less if you understand how it works.
When the power goes out and is later restored, how do you know what time to set your clocks to? Have you ever wondered how time is regulated? Learn how scientists determine exact time.
About 90 percent of Americans consume some form of caffeine every day: It's our most popular drug by far. What's so special about this stimulant?
Helium balloons tend to fascinate adults and children alike (and it's not just the Donald Duck voice thing, though that is a big draw). Learn all about helium and why it floats!
Pi is an extremely interesting number that is important to all sorts of mathematical calculations. Did you know it can be calculated without the use of circles? Find out how you can calculate it yourself.
Radar seems to have infinite uses: Police use it to clock your speed, NASA uses it to follow satellites, meteorologists use it to track storms and the military uses it to track the enemy ... Learn all about radar technology!