Category: Beginner

Lava from volcano.

The Leidonfrost Effect is cool

You can test the Leidonfrost Effect at home right now. Check out this video. Ever dip your hands in molten lead? (Skip to around 4 min) Ever dip your hands in liquid nitrogen? The explanation All three phenomena are a result of the Leidonfrost effect. The explanation is pretty simple. […]

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Learn Projectile Motion (Again)

Projectile Motion is the most classic high school physics problem in existence. It might be a little bit boring, but it’s very important to master, and it’s a great way to apply what you’ve learned in kinematics. Here’s the set up. First of all, what are the forces acting on the ball […]

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A glass of hot chocolate.

The Hot Chocolate Effect

The hot chocolate effect The Hot Chocolate Effect is a cool little experiment you can try at home right now. Take a cup of hot water and tap a spoon against the bottom of the glass. Then add your favourite hot chocolate powder and stir it in. Now tap at the […]

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A plasma sphere

Energy of a Charged Sphere

In this problem, you’ll be calculating the energy of a charged sphere. This can be pretty hard if you’ve never done anything like it before. But it’s super easy once you know the trick. Give it a shot! You have a solid metal ball with a total charge and a […]

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Two springs in series

How to Solve Springs in Series

Most physics students have studied springs before, but not many have studied springs in series. Did you know that having  identical springs end to end actually makes a new spring that’s half as strong? Cool right? How do you figure this out? Take a look at the diagram above and see […]

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If your car is travelling at the speed of light, how fast are your headlights moving?

This is a classic problem in relativity. Let’s rephrase it a little bit for clarity. Let’s say is moving past at the speed of light and is moving past at the speed of light. and are all moving in the same direction. How fast is moving relative to ? I’ll give […]

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Cruise ship staying afloat because of buoyancy

Explaining Buoyancy Once and for All

Buoyancy is everywhere in our everyday lives. Boats can sail above the water, hot air balloons rise up into the sky, and (most) humans are able to swim. In this lesson, I’ll try to explain what exactly buoyancy is, and how you can calculate it. If you’re an absolute beginner, read the first part. If you’re […]

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Tennis ball on top of basketball

How does it bounce that high?

Want to see something amazing? Check out this video (skip to 20s). Here’s the problem statement: You stack a super bouncy tennis ball on top of a super bouncy basketball as shown in the image below. The bottom of the basketball is at a height above the ground. The balls […]

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