Come for the cat video, stay for the science…

This showed up in my Facebook feed the other day.

As I watched this video about six or seven times in a row, you know I couldn’t help but consider the physics behind the poor kitty’s plight. We’ve discussed how an object only changes its motion (starts moving, stops moving, changes speed, changes direction) if an overall force acts on it. When a cat jumps off the floor, what’s applying the force that allows her to start moving upward?

Oddly enough, the floor is.

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…don’t worry, it’s perfectly normal.

AKA Freebody Diagrams, Part Two.

For a definition of/conceptual take on freebody diagrams and the forces within them, make sure you check out Part One, then head on back here to plug in the numbers.

Let’s begin by reviewing our basic freebody diagram from last time- but with one small change.

Click to enlarge.

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If you’re feeling a little perpendicular tonight…

…or, Freebody Diagrams: Part One.

How does a 27-year-old science enthusiast amuse herself on a Saturday night? By doing things like this:

Tiny Einstein is always watching.

So what on Earth is this? (Besides evidence that I’ve really got to get out more…) This is an elaborate photographic representation of a freebody diagram, which is a visual tool that you can use to analyze the forces acting on an object. In a freebody diagram, you draw arrows to represent the strength and direction of all the forces acting on an object. The standard introductory freebody diagram has four forces in it:

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