Questions for you

Relative Humidity Lab

Here is a map of where we collected relative humidity data today using slide psychrometers. It was a fun day. Each placemark on this map displays the average relative humidity from data collected during 3rd, 4th, 6th, and 8th Periods.

View Relative Humidity Lab in a larger map
Overall, the average humidity outside was 73%. All relative humidities taken inside the building were averaged as well, and the result was 68%.
The relative humidity according to the National Weather Service was 45% this afternoon. What could have caused the discrepancy? Why do you think our humidity values were higher?

Humidity Questions

Here are the essay questions about humidity that you can complete anytime today or tomorrow on Classmarker.

1. Suppose it is summer (YES!!) and you plan to have a glass of iced lemonade outside. You notice that water drops begin form on outside of the glass. Why does this happen? Where does this water come from? (2 points)
2. A person's body tends to sweat more on a humid day than it does on a dry one, even if the outdoor temperature is exactly the same. Why does it happen this way? (Hint: Your answer should include how evaporation changes the temperature of the air.) How does this relate to how we measure relative humidity? (Hint #2: Would a large difference between dry-bulb and wet-bulb temperatures signify dry weather or humid weather?) (4 points)

How do you crush your cans?

This is what I do. Here's the procedure:

• Place 8-10 ml of water in an empty pop can.


• Place the pop can onto the heat source and wait for the water to boil. After you see steam escape, continue to boil for one minute.


• Use the tongs to remove the can from the heat. Quickly turn it upside-down and place it into a saucer with water (which was close-by).

As Mr. Hoegh goes through this lab demonstration, please answer the following questions in a blog comment.

1. When heating, what kind of air pressure was inside the pop can -- high or low? Explain why you believe this to be true.


2. Once the heated can was placed into the water, what kind of air pressure was on the outside of the can -- high or low?


3. What caused the can to be crushed? Why did we need the water seal?

After completing these questions in your comment, go through some "Pressure" flash cards on Ediscio, or look at the following pressure websites. Otto von Guericke makes a vacuum Toricelli's Barometer video Air Pressure Balloon Animation Storm System Animation

Standardized Advice

Standardized Advice from Owen Hoegh on Vimeo.

This video includes why you want to do your best, how you can do your best, and what your frame of mind should be.

Study Island and Ediscio

There are a couple of ways in which you can study for the upcoming Dakota Step Science test during these next two days of shortened classes. Here they are:

Study Island: Go here to practice the skills you'll need on Friday. Below are the directions.

VIDEO EXPLAINING WHAT TO DO NEXT

• To sign in, the username is “tie2011”, and the password is “trial”.


• Scroll down and click on the link that says “Science (middle)”. The new page will have a bunch of learning statistics.


• Place a checkmark by the different standards you want to learn. (You should select ALL of the Standards in Content Standard D: Earth and Space Science, and "Classifications of Matter", "The Periodic Table", and "Matter: Changes and Conservation" in Content Standard B.)


• After you check those, click on the “Start Studying” link, and do exactly that. It is not a big deal which standards are chosen, but these questions fit the style of questions you might see on Friday.

Ediscio Flash Cards: Look through the flash cardboxes and your learning statistics. Guide yourself through a crash course of flash cards. Which concepts do you need to take a look at? The list of cardboxes, along with the quarter we studied them, is HERE.

Air Pressure is the Best Around

Air Pressure is the Best Around from Owen Hoegh on Vimeo.

Air pressure on top of a newspaper provides enough leverage to sever a piece of wood.

Global Winds Simplified

Global Winds from Owen Hoegh on Vimeo.

This is a lesson about global winds, which are explained through simple questions about pressure, density, and temperature.