Seasons - Day Length

Transcription

1 Seasons - Day Length Name Period Date Procedure: s: 1. Use a mini-trundle wheel to measure the whole circumference (in cm) of the world at the. 2. Record the measurement in the table for the each date in the column. 3. Repeat the whole circumference measurements for the other 4 latitudes (the, the Equator, the, and the ). s: 1. While standing in between the sun in the center of the classroom and one of the dates on the wall, hold the globe so the north pole is titled toward the back of the classroom. 2. Measure the part of the circumference (in cm) at the that is lit by the sun. This represents the amount of hours of daylight this latitude will get on that day. 3. Record the measurement in the column. 4. Repeat for each of the latitudes. Hours of : 1. Calculate the percentage (%) of daylight and number of daylight hours by following the formulas in the table o N June 21 () Hours of on June 21 () % = hours = % x

2 () 66.7 o N September 20 () Hours of on September 20 () () % = hours = % x

3 66.7 o N December 21 () Hours of on December 21 () () % = hours = % x

4 66.7 o N March 20 () () Hours of on March 20 () % = hours = % x

5 Conclusion/nalysis: 1. On what day do the following latitudes have the highest number of daylight hours????? 2. Explain why some of your answers in question #1 are on different days. 3. On what day do the following latitudes have the lowest number of daylight hours????? 4. Explain why some of your answers in question #3 are on different days. 5. What do you notice about the hours of daylight for March 20 for those 5 latitudes? 6. What do you notice about the hours of daylight for September 20 for those 5 latitudes? 7. Explain why the answers for questions #5 and #6 are that way. 8. So, who cares? I mean, what does it matter if there are more daylight hours at some times of the year than others? What does that have to do with the seasons? nswer this question: How does a higher number of daylight hours affect the coldness and hotness of our weather?

6 9. What do you notice happens to the number of daylight hours on June 21 as you go from the south pole to the north pole? Explain why that is. 10. What do you notice happens to the number of daylight hours on December 21 as you go from the south pole to the north pole? Explain why that is. 11. Fill in the table below. Hint: fill in the June 21 and Dec 21 data first. Northern or Southern Hemisphere? What Season is it on March 20 June 21 Sept 20 Dec 21 Tropic of Cancer Equator Tropic of Capricorn What if the Earth weren t tilted? What would happen if we took away the tilt of the Earth making a tilt in the Earth? Let s look at how that would affect the Earth. You can use a globe to help you visualize, but it is not necessary to re-measure all the data. 1. On what date(s) would your city have 12 hours of day and 12 hours of night? 2. On what date(s) would your city have the highest number of hours of daylight? 3. On what date(s) would your city have the lowest number of hours of daylight? 4. What would the seasons be like on earth if the earth had no tilt?

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