Question

Nome_ Nome Date CONCEPT CONGEPTUAL Physical SciencE eChapter 24: The Oceans, Atmosphere, and Climatic Effects PRACTICE SLET Chap T Earth The Earth's Seasons Here w apple. part of part of that cc L. The warmth of equatorial regions and coldness of polar regions on the Earth can be understood by considering light from a flashlight striking a surface. If it strikes perpendicularly, light energy is more concentrated as it covers a smaller area; if it strikes at an angle, the energy preads over a larger area. So the energy per unit area is less. Draw Moor d, exx The arrows represent rays of light from the distant Sun incident upon the Earth. Two areas of equal size are shown, Area A near the north pole and Area B near the equator. Count the rays that reach each area, and explain why region B is warmer than region A 2. The Earth's seasons result from the 23.5-degree tit of the Earth's daily spin axis as it orbits the Sun. When the Earth is at the position shown on the right in the sketch below (not shown to scale), the Northern Hemihere tilts toward the Sun, and sunlight striking it is strong (more rays per area). Sunlight striking the Southern Hemisphere is weak (fewer rays per area). Days in the north are warmer, and daylightlasts longer. You can see this by imagining the Earth making its complete daily 24-hour spin. Do two things on the sketch: (1) Shade the Earth in nighttime darkness for all positions, as is already done in the left position.(2) Label each position with the proper month- March, June, or December. Be sure to do the shading before you answer questions on the backside of this sheetl 165 The Earth's Seasons-continued a. Whe n the Earth is in any of the four positions shown, during one 24-hour spin a location at the equator receives sunlight half the time and is in darkness the other half of the time. This means that regions at the equator always get abouthours of sunlight andhours of darkncss. b. Can you see that in the June position regions farther north have longer days and shorter nights? Locations north of the Arctic Circle (dotted in the Northem Hemisphere) are always aluminated by the Sun as the Earth spins, so they get daylight_ hours a day. e. How many hours of light and darkness are there in June at regions south of the Antarctic Circle (dotted line in d. Six months later, when the Earth is at the December position, is the situation in the Antarctic the same or is it the reverse? e. Why do South America and Australia enjoy warm weather in December instead of in June? 3. The Earth spins about its polar axis once each 24 hours, which gives us day and night. lf the Barth's spin was instead only one rotation per year, what difference would there be with day and night as we enjoy them now? If the spin of the Earth was the some as its revolution rete around the Sun, would we be like the Moon-one side always facing the body it orbits? n Section 24.3 read ahead about gravity lock and why the Moon shows only one face to Earth. 166

Answer 1

a. 12 hours of sunlight and 12 hours of darkness.

b. 24 hours a day.

c. There are 24 hrs as dark and 0 hours as light.

d. After the 4 months the situation is reverse.

e. Australia and South America are in Northern hemisphere as Earth axis is tilted this time Northern Hemisphere.

3. The earth rotation will be around 1 year then it will be 4 months as complete day and 4 months as complete night around earth with changing seasons.

* In the last dialogue from the image of the earth if the spin of earth were same as the revolution rate the sun then only one side of the earth always faces sun and the other is always away from the sun

that is the said statement is true.