7 th Grade Science Unit: Water s Cycles and Patterns Lesson: WCP 12 Name: Date: Thursday, September 15 2016 Homeroom: OBJECTIVES: By the end of today s lesson, you will be able to SWBAT describe and calculate relative humidity. SWBAT define weather and list its components. DO NOW Earth 1. List the layers of the atmosphere from Earth s surface to outer space Outer Space Word Bank Mesosphere Stratosphere Troposphere Thermosphere Directions: Fill in the blank with the correct word. Word Bank Radiation Convection Conduction 2. When you touch a cup of hot chocolate and can feel the heat on your hand, you are experiencing. 3. When water boils, the water on the bottom gets hot first and rises. This pushes the colder water down. This is an example of. 4. The invisible waves of energy that the Sun sends to Earth is called 1
Practice Beyond Perfection!!! Look at each picture and explain how the heat is being transferred. Picture Process Description 2
I DO CLASS NOTES is the current state of the atmosphere, including temperature, wind speed, humidity, precipitation and cloud cover. How does weather relate to the water cycle? Humidity As we learned last unit, water is always being moved from the Earth s surface, into the atmosphere, and back to Earth. This cycle is important for understanding weather. The water cycle is what gets water vapor into the air. Without water vapor.there is no weather! As water evaporates from lakes, oceans, and plants, it becomes water, or moisture in the air. The amount of water vapor in the air is called a. As water evaporates and becomes water vapor, t he humidity of the air. b. The air s ability to hold water vapor changes as the of the air changes. As the temperature of air increases, the air s ability to hold water vapor. Concept Check Can the air hold more water vapor on a hot day or a cold day? 3
Relative Humidity is the amount of water vapor compared with the of water vapor the air can hold at a certain temperature. a. Relative humidity is given as a. b. When air holds all of the water that it can at a given temperature, it is said to be. This is 100% relative humidity. Relative Humidity Formula Relative Humidity = amount of water in the air Maximum amount of water the air could hold Saturated air has a relative humidity of 100%. What if 1 meter cubed of air can hold 12 grams of water. Currently, that meter cubed of water holds 12 grams of water. Prove it with Math!! What if 1 meter cubed of air can hold 12 grams of water. Currently, that meter cubed of water holds 6 grams of water. What is the relative humidity? Prove it with Math!! What if 2 meters cubed of air can hold 10 grams of water. Currently, those 2 meters cubed of air are holding 3 grams of water. What is the relative humidity? Prove it with Math!! 4
WE DO: Guided Practice What are 2 factors that affect relative humidity? 1. The amount of in the air. a. If the temperature does not change, relative humidity will change if water vapor is or of the air. b. The water vapor there is in the air, the higher the humidity will be. c. The water vapor there is in the air, the lower the humidity will be. 2. Temperature a. If the amount of water vapor in the air stays the same but the temperature changes, the relative humidity changes. a. The relative humidity as the temperature. b. The relative humidity as the temperature. Concept Check If 1 meter cubed of air can hold 10 grams of water but is currently holding 7 grams of water, what is the relative humidity? If water is removed from the air, what will happen to the relative humidity? If the amount of water stays the same, but the temperature increases, what will happen to relative humidity? 5
YOU DO: Independent Practice If 1 meter cubed of water can hold 20 grams of water, but it is currently holding 12 grams of water, what will the relative humidity be? If 2 grams of water are added to the air, what will the new relative humidity be? Water was put into the air, what happened to the relative humidity? Relative humidity Increased / Decreased What would happen to relative humidity if the amount of water in the air stayed the same, but temperature decreased (it got colder)? Relative humidity would Increase / Decrease Yesterday, the relative humidity in the morning was 50%, the amount of water vapor in the air did not change. However, by the afternoon, the temperature increased by 10 degrees. When the temperature increased, did the relative humidity increase or decrease? 6
Directions: Use the graph below to answer the questions. 1. At 0 C, how many grams of water can each cubic meter hold? 2. At which temperature can air hold the most water? a. -20 C b. -10 C c. 0 C d. 20 C 3. Based on the graph, complete the following sentences: The higher the temperature of air, the The lower the temperature of air, the More water vapor can be held by air. 7
1. The maximum amount of water that this air can hold is 10 grams. Right now, the air is holding 2 grams of water. What is the relative humidity? 2. The maximum amount of water that this air can hold is 20 grams. Right now, the air is holding 10 grams of water. What is the relative humidity? 3. When you woke up one day it was 10 F. When you left school, it was 15 F. If the amount of water in the air did not change, what happened to the relative humidity? Did it go up, or down? 4. On Saturday, temperatures dropped during the day from 30 F to 16 F. What happened to the relative humidity throughout the day? 8
7 th Grade Science Name: Date: September 15, 2016 Unit: Water s Cycles and Patterns Lesson: WCP 12 Homeroom: /5 = % DNG? Strive Due Date: A B C D F Directions: Answer the question below. No complete sentences. (1/4 pt. each) 1. What 2 things do you need to know when deciding if the relative humidity has changed? a. b. 2. If the amount of water vapor in the air stays the same AND the temperature goes down, what will happen to the relative humidity? (Circle one) a. Relative humidity would increase b. Relative humidity would decrease 3. If the amount of water vapor in the air stays the same AND the temperature goes up, what will happen to relative humidity? (Circle one) a. Relative humidity would increase b. Relative humidity would decrease 4. If the temperature stays the same and the amount of water vapor in the air increases, what will happen to relative humidity? (Circle one) a. Relative humidity would increase b. Relative humidity would decrease 5. If the temperature stays the same and the amount of water vapor in the air decreases, what will happen to relative humidity? (Circle one) a. Relative humidity would increase b. Relative humidity would decrease 6. Define weather: 9
Relative Humidity Formula Relative Humidity = amount of water in the air Maximum amount of water that air could hold If 1 meter cubed of water can hold 16 grams of water, but it is currently holding 8 grams of water, what will the relative humidity be? Show your work: Answer: % If 4 grams of water are taken out of the air, what will the new relative humidity be? Show your work: Answer: % Water was taken out of the air, what happened to the relative humidity? Relative humidity Increased / Decreased What would happen to relative humidity if the amount of water in the air stayed the same, but temperature increased (it got hotter)? Relative humidity would Increase / Decrease Yesterday, the relative humidity in the morning was 30%, and the amount of water vapor in the air did not change. However, by night, the temperature decreased by 10 degrees. When the temperature decreased, did the relative humidity increase or decrease? (1/2 point) 10