How to Measure the Calories in a Candy Bar—With Physics!
This Halloween, when you grab a candy bar, pay attention to the wrapper. In the United States, a “nutrition facts” label has been required for all packaged foods since 1994, …
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The Physics of Faraday Cages
This also works the other way: Incoming electromagnetic waves will get canceled by the moving charges in the Faraday cage. Your phone won’t know that it’s getting a text message …
Which Spider-Man Is Stronger: Tobey Maguire or Tom Holland?
Next, I need the mass. Each car has an empty mass of 26,000 kilograms and a capacity of 34 seats, or 123 total passengers. From the clip, the train looks …
Radiation Is Everywhere. But It’s Not All Bad
For many of the sources you encounter in everyday life, the amount of radiation is so low that you don’t need to worry about it. But ionizing radiation can also …
How to Cool an Object Without Using Any Energy
There are three ways that objects can have a thermal interaction with other objects. The most common method is through heat conduction. This happens when two objects of different temperatures …
When You Drop a Rock Overboard, What Happens to the Water Level?
Physics questions are the most fun when people don’t immediately agree on the answer. What feels intuitive or obvious—sometimes isn’t. We can argue over the solution for hours of entertainment, …
OK Surfers, How Much Would It Cost to Power Your Own Wave?
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That expression doesn’t look nice, but at least now the energy calculation is in terms of things that we actually know or can estimate. All we need to do is …
All the Ways to Slow a Car (Even Some Bad Ways)
.jpg "All the Ways to Slow a Car (Even Some Bad Ways)")
Since the vehicle is moving up the incline and gravity only pulls straight down, there is a component of this force that pulls in the opposite direction as the velocity …