Unit Three: Lessons 1-3

Lesson 1

In lesson one we learned about weather, which is a state of atmosphere in a region over a period of time. Weather is the result of the interaction between Earth, water, the atmosphere and the Sun. There are many ways to describe weather and what it is doing.
Jetstream: High level in the upper atmosphere and moves across the U.S from west to east
Cloudcover: Areas covered by clouds
Fronts: Different waves of air, displayed on a line. Circles are warm and triangles are cold
Precipitation: Rain or snow

Practice Problems
2. A planet must have an atmosphere.
3. A physical change is when a substance changes forms, temperature, shape etc.

Lesson 2

Lesson 2 talked about proportions. Two variables are proportional when you can multiply the value of one by a constant to get the value of the other. When something is proportional the number that represents the 2 variables is represented by k. Volume increase is predictable. The height of rain is not dependant on the diameter of the container but the volume of rain is.

Practice Problems
3. The height will be the same but the volume will be different because the containers are different sizes.

Lesson 3

In lesson 3 we learned that density= mass/volume. The denisty of water is 1 gram per milliliter. Both snow and ice have densities that are less than water. If a substance changes phases it changes density.

Practice Problems
4. More because ice has a smaller density than water. When it melts the density increases so the volume would have to iincrease as well.
9A. Lead has a greater volume because it is more dense than iron.