Make any needed corrections. Say the different directions out loud, and ask students to point where the direction is on a compass wheel or on a makeshift wheel outside.
You can also hand out cards with directions for students to place on the wheel. For older students, ask them to determine more precise directions, such as northwest or southeast.
Have the students make direction markers and post them on the walls of the classroom. Double check the location with a compass.
Explain to students how to use maps. Demonstrate several types of maps, such as topographic, city, or state maps. Ask students to list what information they can get from a map, such as directions, landmarks, and building projects. Ask students to work together to determine which map would be best to find their way in the following scenarios:. Practical: Test your students' understanding of directions and mapping by taking them outside and asking them to point or position cards in the directions you say aloud such as east, west, or southeast.
Assessment: How did your students do? Here are some ways to assess your students' comprehension, reflective of grade level. Teach students about mapping latitude and longitude lines using GPS units. This lesson is split into three parts. The first part focuses on an activity of mapping the schoolyard to engage students, the second part introduces GPS units and how to use them, and the final part ties the others together by getting students to pinpoint exact locations on the schoolyard map.
Prelesson Preparation: Create a rough diagram of your schoolyard on a 4-foot-square piece of colored paper. You will add landmarks and points of interest later.
Ask students to sketch a map of the schoolyard in their field journals, noting important landmarks and geography. Brainstorm different elements they'd like to include on the map, such as flagpoles, swings, trees, baseball diamonds, or lights. Each student will draw the object listed on his or her note card on small pieces of paper. They will add these to the schoolyard diagram. Ask students to attach each item to the diagram where they think it belongs. Use transparent tape so students can move the objects around easily in the next section.
Ask students how they can validate the location of objects placed on the diagram in the previous activity. Brainstorm possible answers. Refer to the NM data-collection form, and point out the section on taking latitude and longitude.
Pair students together, and equip each pair with a GPS unit. Explain that one student will read the unit while the other student records readings in his or her field journal. Ask students to walk the schoolyard from south to north, writing latitude numbers every 50 feet as directed. Return to the classroom and ask students what they observed and whether there was a number pattern.
Explain to students that they'll use the GPS unit to test the precision of objects placed on the schoolyard map.
Take latitude and longitude numbers as a group around different points of the schoolyard -- at the corners and around the perimeter every 10 feet or so. The sun rises in the east and sets in the west. So in the morning, the sun will be in the east; in the afternoon, it will be in the west.
At night, the North Star in the Northern Hemisphere points north. The Southern Cross , which is a constellation , or group of stars, marks south in the Southern Hemisphere. The arrow is a universal symbol for direction. If someone needs to turn right at a stop sign to get to the freeway , there will usually be an arrow pointing the way. Photograph by Mel Garrett , My Shot.
A simple compass can be made by floating a magnetized needle on a leaf in a dish of water. You can magnetize a needle by rubbing it with silk or a magnet. The audio, illustrations, photos, and videos are credited beneath the media asset, except for promotional images, which generally link to another page that contains the media credit. The Rights Holder for media is the person or group credited. Caryl-Sue, National Geographic Society. Dunn, Margery G.
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It can take more than a day for such residual currents to subside completely. If all extraneous influences including air currents can be reduced below a certain level, one apparently can observe that drains do consistently drain in different directions in the two hemispheres.
Finally, Thomas Humphrey, a senior scientist at the San Francisco Exploratorium, discusses in more detail the reasons why we do not see the Coriolis effect at work in the bathroom:. For a fee, they will allegedly demonstrate that the toilets flush in opposite directions. It is only for show, however; there is no real effect.
Yes, there is such a thing as the Coriolis effect, but it is not enough to dominate the flushing of a toilet--and the effect is weakest at the equator. Coriolis acceleration at mid-latitudes is about one ten-millionth the acceleration of gravity. Because it is a very small acceleration, it needs a very long distance for it to produce an appreciable curvature--and hence directionality--to the motion. A toilet or sink is just not large enough.
The Coriolis effect influences because wind velocities may be hundreds of times greater than the motions in a sink and because the distances involved are far larger than the tiny draining diameter in a sink or toilet. The net motion in the water becomes much more pronounced as the water is forced to move in toward the center of evacuation, causing the normally invisible flows in the water to become visible as the water nears the drain.
The ultimate direction of that flow is random--it can go one way one time, the other way the next. But you will find that the faucet is almost always off center or that there is some other asymmetry in the sink. As a result, filling the sink consistently gives it some net rotation in the same direction, which you see as the normal direction of evacuation. Toilets will always drain and fill the same way, for the same reason.
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