Consider the following statements a 1 only c 1 and 2 1. Small tides occur when the moon, earth a High and low tides are regular phenomena. Tides are formed mainly due to the gravitational force of attraction between water, the sun and the If it is high tide where you are, is the tide high or low on the side of Earth directly opposite you Are these Answers Helpful?
Yes No. Disclaimer The questions posted on the site are solely user generated, Doubtnut has no ownership or control over the nature and content of those questions. Latest Videos. By using this site you agree to the use of cookies. Check our Cookie Policy for more details. Jett Helping Hand. At both new and full moons lunar phases the tides are most pronounced for example, the highest high tides. Kayson Helping Hand. Answer:At both new and full moonsExplanation: Depending on the position of the two stars in relation to our planet, the tides have different behaviors.
This is where the lunar phases come in. Depending upon the positions of the sun and moon relative to the Earth, the sun's gravity may enhance or diminish the tidal effect caused by the moon.
When the sun and moon are aligned at the time of full moon or new moon , their gravitational forces act in the same direction and produce more pronounced high and low tides that are called spring tides.
When the sun and moon are at right angles relative to the Earth, the gravitational force of the sun partially cancels out the gravitational force of the moon. The result is less pronounced high and low tides that are called neap tides. For centuries, people who live and work near seacoasts have understood the importance of being able to predict tides and tidal currents.
Low tides may prevent ships from entering harbors, while high tides may make it impossible for ships to pass beneath bridges. Tidal currents may significantly increase the speed of a vessel, or may carry it into dangerous waters. Recreational boaters who anchor near shore may find themselves stranded by a falling tide.
Fishermen throughout the world have learned that catches are likely to be much larger during certain portions of the tidal cycle than others. Many people who live thousands of miles from any ocean also pay close attention to the same lunar cycles that produce tides. Traditional agricultural practices often prescribe planting and harvesting during times when the moon is at a specific location relative to the Earth. Some traditional forestry practices link lunar cycles with specific properties of wood including strength, resistance to decay, and resonance for musical instruments.
Lunar cycles have also been linked with many aspects of human biology, behavior, and folklore including crime, suicide, mental illness, birthrates, fertility, werewolves, and vampirism. In this lesson, students will research and analyze various phenomena in living organisms that have been attributed to lunar cycles. If you choose to have students work in groups, you may want to assign different tutorial sections to each student.
Have each student or student group answer questions in the Tides Subject Review. To save class time, you may want to assign this portion of the lesson as homework. Lead a discussion of students' answers to the questions, highlighting ways in which knowledge of tides can be useful and important. Have student groups research and prepare written reports on at least three phenomena in living organisms that are allegedly affected by lunar cycles.
Assign one of the following topics to each student group:. Tell students that in addition to their assigned topic, they should identify and report on two additional phenomena in living organisms that are allegedly affected by lunar cycles.
Reports should include hypotheses or discussions of the mechanism s through which lunar cycles might affect the phenomena being discussed. Have each student group present an oral presentation of their research results and analyses.
When all groups have made their presentations, lead a discussion of the pooled results. Reports should reflect a mix of well-documented effects of lunar cycles, as well as "effects" that have no demonstrated factual basis. Discuss possible reasons for widespread belief in "effects" such as emergency room admissions for which there is little or no supporting evidence.
Encourage students to discuss how the same factors may affect other popular perceptions about natural phenomena and scientific investigations. Be sure students realize that lunar cycles almost certainly are important in the timing of some phenomena such as reproduction in many marine animals.
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