1. Do Now’s
Weather Unit

2. Which direction does heat transfer?
Do Now # pg 65
Draw a picture in the boxes showing the kinetic energy of hot air and cold air.
Which direction does heat transfer?
What happens when molecules gain energy? Lose energy?
Hot air
Cold air
As temperature increases density decreases. When molecules gain kinetic energy they move faster and bump into each other with more force. This collision forces them to spread further apart decreasing their density). If you are running around you need more space vs. if you are just standing still.
Objects that are more dense than water will sink and less dense will float.
Cold air should be drawn with more molecules closer together with less kinetic energy and Hot air should have fewer molecules more spread apart with more kinetic energy.

3. Do Now # pg 65
Draw a picture in the boxes showing the kinetic energy and density of hot air and cold air.
Are the molecules closer together or farther apart in hot air? Why? Give an example.
Hot air
Cold air
As temperature increases density decreases. When molecules gain kinetic energy they move faster and bump into each other with more force. This collision forces them to spread further apart decreasing their density). If you are running around you need more space vs. if you are just standing still.
Objects that are more dense than water will sink and less dense will float.
Cold air should be drawn with more molecules closer together with less kinetic energy and Hot air should have fewer molecules more spread apart with more kinetic energy.

4. What is the relationship between density and temperature?
Do Now # NEW PAGE!! pg. 68R
What is the relationship between density and temperature?
Which will float, an object that is more dense than water or less dense than the water?
Draw a picture of cold air and hot air.
A - The hotter something is the more likely the density will be ___________________ (higher/ lower).
B - An object that is ___________ dense than water will __________
C - Draw the picture

5. Explain in detail why cold air sinks. Why warm air rises.
Do Now # pg. 68
Explain in detail why cold air sinks. Why warm air rises.
Draw a model to explain how a hot air balloon works.
Explain why scuba divers need a weight belt. (a belt they wear to make them heavier)
Cold air sinks because it has more density. Warm air rises because it has more thermal energy and less density. Therefore it can escape the lower atmosphere.
B. Draw a hot air balloon with the basket at the bottom, and the fire thingy in the middle with the silk balloon at top.
C - Scuba divers need a weight belt because the density of a diver’s body is not high enough to cause the diver to sink.

6. Do Now # NEW PAGE 71
Are the following statements true or false. Explain why!!!!
Matter that is less dense than the surrounding matter sinks.
Air that is warmer is less dense and rises.
Solids have more kinetic energy than liquids of the same matter.
Hot air is heavier than cold air.

7. Explain evaporation in detail. (use density, weight and temperature)
Do Now # pg. 50
Explain evaporation in detail.
(use density, weight and temperature)
Why do clouds form?
Evaporation is when liquid water gets heated up and turns to water vapor in the air. This warm water vapor mixes with the warm air molecules and rises because it is less dense. It rises into the upper layers of the atmosphere
The warm water vapor and air that rises into the upper layers of the atmosphere begins to slowly transfer it’s kinetic energy to colder molecules in the air. As the warm molecules loose energy they begin to cool and become more dense. When the water vapor looses enough energy it turns into water in the sky creating clouds. (condensation)

8. What type of weather do H pressure systems bring? Why?
Do Now # pg. 50
What type of weather do H pressure systems bring? Why?
What type of weather do L pressure systems bring? Why?
If the air is cold does it put more or less pressure on the earth than warm air?
Does air in H pressure systems rise or sink?
High Pressure systems bring clear sky because the cold more dense air is heavier so it sinks to the ground bringing all the moisture with it.
Low pressure systems brings precipitation because it is less dense and rises as it rises it carries all the water vapor into the upper layers of the atmosphere where it cools and condenses creating clouds.
If the air is cold it puts more pressure on the Earth because it is more dense and heavier therefore having more molecules to apply pressure.
High pressure systems are made of cold sinking air.

9. Do Now # 5 pg. 54 Which way is the wind blowing in the picture above?
Location A
Location B
Do Now # pg. 54
Which way is the wind blowing in the picture above?
What would the name of the wind be?
Why does hot air rise? Cold air sink?
As you rise higher into the atmosphere does it get colder or warmer? Why?
From location B to A therefore blowing east to west or blowing west because wind always blows from High pressure to low pressure.
East wind because you name winds from where they are coming from.
Hot air rises because it is less dense and lighter than the surrounding air causing it to rise. Cold air sinks because it is more dense and heavier than the surround air.
It gets colder as you rise further into the air because the sun’s radiation heats the earth and the warm air rises from the land. The further you are from the earth the colder it is.

10. Do Now # pg. 54
During the summer why do we get a sea breeze during the day but a land breeze at night?
If you look at a weather map and see a big L above Culver City what kind of weather can you expect?
If you measure the pressure on a cold day would you expect to see a high pressure reading or a low pressure reading? Why?
What happens to Density as Temperature increases? Why?
The reason that the wind changes direction is because during the day the air over the land is hotter creating less pressure and the wind blows from high pressure to low pressure causing the wind to blow towards the land but at night the land cools quickly so the wind blows towards the sea now because the air over the sea now has less pressure.
I would expect precipitation if there is enough water vapor in the air.
On a cold day I would expect to get a high pressure reading.
As temperature increases density decreases. When molecules gain kinetic energy they move faster and bump into each other with more force. This collision forces them to spread further apart decreasing their density). If you are running around you need more space vs. if you are just standing still.