Diameter

Where r is the radius of the sphere.

It has a very easy relationship with the radius.

That's a, that's a ninemile radius.

Try to measure a circle.

If you were to put a tape measure to go around it and someone were to ask you what is the diameter of the circle?

Vertical spacing

Circle radius

Vertical Radius

Vertical Radius

dabs per actual radius

We call this distance along the widest point of the circle, the diameter.

Now what is the radius?

Radiotelescope diameter

These are just stars.

We call that word the circumference of the circle.

Regardless of what kind of ID gripping jaws you are using

Or another way to visualize it

What is the diameter of the circle?

Now, let's ask another question.

Actually, never!

Use a slip of paper, and bring the tool to the jaw face, until the paper is pinched by the insert tip

But this the current version of it, is a flying airship that is about 35 meters in diameter, about 110 feet in diameter.

Well, that's the same thing as g plus h.

To the bottom of a muddy riverbed

We can zoom out even more... and over here, so you had the Virgo Supercluster, 150 million light years, in the last diagram, this diagram here, I'd like to keep both of them on the screen if I can, this diagram right here, 150 million light years across, that would fit right about here, on this diagram.

I wanted it to convey some proportions that I was interested in, which is the diameter of the Moon and the diameter of the Earth in proportion to each other.

The pond is 100 meters in diameter.

The hole is two meters across.

We will use the adjustable boring ring again to hold the jaws while making this initial bore

The lake is three miles across.

Or the horizontal radius is going to be 3.

Apophis is going to hit us.

Our No.4 is Enceladus, one of Saturn's inner moons.

We can multiply both sides of this by the diameter and we could say that the circumference is equal to pi times the diameter.

And I did one that was about 35 feet long.

The lake is four miles across.

(Laughter)

You get some sense of the size

Think! Orbit diameter of your planet?

We set the remaining values conservatively based on the insert we're using to cut these steel jaws

Hellas Basin.

And then you see that the horizontal axis, I guess.

Or the horizontal diameter, is going to be 3.

OK, this is a neat property of circles.