1. March 19, 2009
The original force between 2 objects is N. The mass of object one tripled, while the mass of object two remained the same. Also, the objects are five times further apart from each other. What is the new force?
2. What do you know about tides?

2. Goals
To explain how tides are formed

3. Q: What’s the deal with tides?
Gravity of both the moon and sun pull on the Earth to make the tides occur.
The moon’s gravity has a larger influence on tides.
The gravitational pull of the sun is greater (it’s more massive), but it is too far away to have a big influence.

5. Q: What’s the deal with tides?
As the moon passes over the ocean, there is a swell in the sea level. As the moon passes to the other side of the planet, the swell occurs there.
High tide on one side of the Earth means low tide on the other side.
Imagine sloshing water around in a container or in a bathtub.

6. Q: What’s the deal with tides?
Tides are not affected by the phase of the moon.
No matter the phase, the moon is the same distance away and has the same mass, so the pull of gravity stays the same.

7. Tasks
Work on Cartoon Guide Notes Sheet (you cannot take this with you!)
Tides WS (due tomorrow)