yego.me
💡 Stop wasting time. Read Youtube instead of watch. Download Chrome Extension

Measuring angles with a circular protractor | Math | 4th grade | Khan Academy


less than 1m read
·Nov 11, 2024

Measure the angle in degrees. So here we have this blue angle that we want to measure in degrees, and it's sitting on top of this circle. That circle is actually a protractor. Sometimes we see, and maybe what you're used to seeing, is protractors that are more semicircle shaped, something like this.

Those semicircle protractors measure from 0 to 180°, which is good, but a circle is even better. A full circle is better because an angle can measure up to 360°. So, a full circle allows us to measure an angle of any size instead of only an angle up to 180°. Now, the way we're going to measure this angle is the same way we would on a semicircle protractor.

The first thing we want to do is make sure one of our rays lines up to zero. So here's one of our rays, and it's lining up to zero on the protractor. So that's nice; it's already lined up for us. Then we're going to measure the opening all the way to the other ray, to right here.

So, if our angle only measured and opened up this far, it would be a 10° angle. If, let's say, it opened here, it would be a 50° angle. But our angle measures all the way to here, to the 160°. So, 160° is the measure of our angle. And again, when you measure on a circle protractor or any protractor for that matter, you're going to line one ray up to the zero and then measure the opening till you get to the other ray, which in this case opened up to 160°.

More Articles

View All
WET DOGS ---- IMG! #40
Blockhead bunnies and disembodied cat unicorn princesses. It’s episode 40 of IMG! You’ve gotta be careful around ducks. Seriously. But it’s okay to be smug with a panda. If you’ve got extra time, carve Lincoln out of Oreo filling. Or check out more of Sa…
TAOISM | How to Get Drunk on Life
The habit of drinking is deeply ingrained in Western culture. Being drunk is often seen as a blissful state in which our sorrows are washed away, and exchanged for courage and an extraordinary ability to be merry and happy. Yes, alcohol loosens the inhibi…
Jacksonian Democracy part 1
When we talk about the big social movements of the early 19th century in the United States, you can’t deny that the emergence of Jacksonian Democracy is one of the most influential aspects of early 19th century culture. So, what was Jacksonian Democracy,…
Types of catalysts | Kinetics | AP Chemistry | Khan Academy
A catalyst speeds up a reaction by lowering the activation energy, and there are many types of catalysts. First, we’re going to look at enzymes, which are biological catalysts. Let’s say that this represents our enzyme, and the place where the reaction oc…
Index Fund Bubble in 2022? Michael Burry vs Warren Buffett
Index funds: A passive investor’s dream. Make one investment but own the whole market. There’s no doubt that index funds and ETFs are a very clever invention. It’s the easy way to be diversified across the whole market and back stocks as an asset class, a…
Do You Know Yourself? - Mind Field (Ep 8)
[soft dramatic music] - Hi, I’m Michael Stevens, but who are you? Do you even know who you are? Are you your memories? - I don’t remember that. - I don’t remember that at all. - Are you the choices you make? The focus tester is actually a magician. - That…