### Mass

If the mass of an object is greater, it will have __more__ resistance to rotation. Conversely, a light object will spin with more freedom.

#### Example

Think about putting a pencil through the center hole of a ruler. If you push the edge of the ruler, it'll spin about the tip of the pencil.

But, why doesn't the ruler spin forever with infinite speed? Of course, there is something holding the ruler back.

Now, imagine if you had a really big, dense ruler, more like a meter stick. It'd be three times the length and five times as thick. You can expect it'd be rotating differently.

**So would the stick be rotating faster or slower?**

Because the meter stick has more mass, it would be rotating slower than the ruler.

### Radius

If the radius of an object is greater, it will have __more__ resistance to rotation. Conversely, an object will spin faster when the radius of the object is shorter.

#### Example

Think about tetherball. If you've never played, it's a game where you hit a ball back and forth around a pole, which connects to the ball with a rope.

When the game starts, the rope isn't wrapped around the pole. Hitting it means the ball will fly out very far from the pole, taking its sweet time to go all the way around.

As you continue playing, the rope forms more loops around the pole. The ball comes closer and closer inward and takes less time to revolve.

If you're losing--meaning you let your opponent wrap the ball around the pole--it'll be very hard to recover, since the ball is now spinning much faster.

This distance between the ball and the pole is called the radius.