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Concept explainers
Introduction: The Earth rotates in an elliptical path around the sun one full time per year. Seasonal changes occur because the Earth is tilted at 23 degrees on the axis. The seasonal changes depend on the amount of sunlight that reaches parts of the Earth.
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Answer to Problem 1SQ
Correct answer: The northern hemisphere is most tilted towards the sun in summer. Therefore, option b. is correct.
Explanation of Solution
Reason for the correct answer:
In June solstice, the Northern Hemisphere has the longest day and receives direct sunlight. Hence, the Northern Hemisphere is most tilted toward the sun.
Option b. is given as “summer”. Therefore, option b. is correct.
Reasons for the incorrect answers:
Option a. is given as “spring”. In the spring equinox, the lengths of day and night are equal everywhere and sunlight directly falls on the equator. Therefore, option a. is incorrect.
Option c. is given as “autumn”. In the autumn equinox, the lengths of day and night are equal everywhere and sunlight directly falls on the equator. Therefore, option c. is incorrect.
Option d. is given as “winter”. During the winter, the Northern Hemisphere has the shortest day length and is tilted away from the sun. Therefore, option d. is incorrect.
Hence, options a., c., and d. are incorrect.
The Northern Hemisphere is tilted towards the sun during the summer.
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Chapter 47 Solutions
Bundle: Biology: The Unity and Diversity of Life, Loose-leaf Version, 14th + LMS Integrated for MindTap Biology, 2 terms (12 months) Printed Access Card
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