How to Run on the Moon

When the elevator is stopped, the two forces are equal and opposite, and the net force is zero. But if you’re accelerating upward, the net force must also be upward. This means the normal force exceeds the gravitational force (shown by the lengths of the two arrows above). So you feel heavier when the normal […]

How to Convince Your Flat-Earth Friends the Earth Is Round

Illustration: Rhett Allain You can see that we have a right triangle with the hypotenuse equal to the distance from the observer’s eyes to the center of the Earth (R + h), with the other two sides being just R and the distance to the horizon (s). Using the Pythagorean theorem, we can solve for […]

How to Measure the Impact From a Collision

Not only do I get the “shape” of the acceleration curve for the colliding cart, but I also get a maximum acceleration of –6.67 meters per second squared. With that acceleration and the mass of the cart (0.566 kilogram), we get a maximum impact force of 3.73 newtons. This isn’t quite the same value I […]