Air Pressure is Powerful

Grade Level:

• 3rd, 4th, and 5th

Objectives:

• The student will:
  • read and learn the meanings of unfamiliar words using knowledge of root words and prefixes
  • work with a small group of classmates to make a meteorological tool
  • use effective communication skills in group activities
  • present a brief oral report
  • convert inches of Mercury to hectopascals

Estimated Time for Completing Activity:

• 45-60 minutes

Type of Activity:

• Exploratory

National Science Standards:

• Standard A Item 3
  Standard E Item 4 and Item 5
  Standard G Item 1

Virginia SOLs:

• English 3.1, 3.2, 4.1, 4.2, 4.3, 5.1, 5.2, 5.3, 5.4
• Science 4.6
• Math 4.8, 4.9, 5.17

Vocabulary:

meteorology, barometer, air pressure, high pressure, low pressure, formula, calculate, convert, conversions

Materials Needed:

• Students will be divided into groups of four. Each group will need:
  
  directions for constructing a barometer (see illustration)
  a rigid plastic tube (about 30 cm to 45 cm)
  (the tube needs to be heated and shaped ahead)
  rubber or cork stopper with hole to suit tube
  bottom with neck to fit stopper
  green food coloring
  large bottle of water

Strategies and Procedures:

1. You will need a glass with a smooth rim, water, and stiff piece of cardboard. Fill the glass half-full of water, and place the cardboard over the opening of the glass. Holding the cardboard tightly in place, turn the glass upside down. Remove your hand from the cardboard and the upward pressure of the air will keep the cardboard in place and the water in the glass. Now that you have the classes attention introduce vocabulary and facts about air pressure.
2. Today we are going to work in groups and make an instrument that Meteorologists use to measure air pressure. Meteor comes from a word that means "something happening in the sky." A meteorologist studies the atmosphere, weather, and climate of our Earth.
   
   The root word "meter" means a way to measure. A barometer is a weather instrument that measures air pressure.

   The prefix "fore" means before.

   A meteorologist who uses tools and instruments to collect data and study the weather is able to forecast the weather before the weather happens. Discuss the importance of this through class interaction and discussion.

   Air Pressure is the amount of Air that presses down on the Earth. Air Pressure affects our weather. Low Pressure areas are caused by hot temperatures that heat up air molecules making them rise. There is less pressure on the surface of the Earth. High Pressure areas are caused when cool air sinks and presses down on the Earth.

   Air Pressure is measured in hectopascals, inches of Mercury, millibars, and millimeters of Mercury. There are formulas that enable us to convert measurements. Today we are going to learn one formula.

   Before students are grouped explain that each group will have 30 minutes to
   read directions
   assemble a barometer
   write a paragraph describing how to make a simple barometer

   Using the following formula each person in the group will convert the following barometric pressures from inches of Mercury to barometric pressure in hectopascals.

   Formula:      in Hg * 33.86 = hPa

   (1) 29.92 in Hg     (2) 30.09 in Hg     (3) 31.12 in Hg     (4) 28.89 in Hg    

Evaluation Tool:

• Rubic:

  80 points = A

  70 points = B

  60 points = C

  50 points = D

  10 points: the group will work quietly and cooperatively
  10 points: all calculations are accurate
  10 points: barometer assembled correctly following all directions
  10 points: calculations done on paper
  10 points: calculations checked using calculator
  10 points: paragraph punctuated
  10 points: spelling correct in paragraph 10 points: topic sentence and four to five supporting sentences

Extention Activities:

• Use the barometer and record data daily.
  Use the data recorded for a week to make bar graphs and stem and leaf plots.

Barometer Directions:

1. Wet the stopper and tube with warm water, and insert the tube into the hole in the stopper.
2. Insert the stopper with the tube into the neck of the bottle until it seals.
3. Pour colored water into the open end of the tube until the "U" is half full.
4. As the atmosphere pressure goes up, the level in the open end of the tube will fall. As the atmospheric pressure goes down, the water level in the open end of the tube will rise.

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Lesson Plan submitted by Carol Mitchell, Poquoson Elementary School, Poquoson, Virginia, USA, for NASA's S'COOL Project.

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