Which of the following statements is/are correct? 1. Angular velocity for all locations on the Earth's surface is the same while linear velocity varies. 2. Linear velocity is maximum at the equator and minimum at the poles. Select the correct answer using the code given below.
- A.1 only
- B.2 only
- C.Both 1 and 2
- D.Neither 1 nor 2
Correct answer
Explanation
The correct answer is C, Both 1 and 2. Every point on the Earth turns through 360 degrees in the same time, but points nearer the equator travel a longer circle and so move faster.
The Earth rotates once in about 24 hours, so every place has the same angular velocity of 15 degrees per hour. Linear velocity is the distance covered per unit time, and it equals angular velocity multiplied by the radius of the circle a place traces around the axis. That radius is largest at the equator, giving a speed of about 1,670 km per hour, and shrinks with latitude as the cosine of the latitude. At the poles the radius is zero, so the linear speed there is zero, the minimum.
A is wrong because statement 2 is also correct. B is wrong because statement 1 is also correct. D is wrong because both statements describe the Earth's rotation accurately.
Exam tip: Earth's rotation: angular speed 15° per hour everywhere; linear speed about 1,670 km/h at the equator, about 837 km/h at 60° latitude, zero at the poles.
Practice Questions
View allWeathering, mass wasting, erosion and transportation are indicators of which one of the following processes?
- A.Denudation
- B.Endogenetic process
- C.Diastrophism
- D.Mountain building
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Weathering, mass wasting, erosion and transportation together wear down and strip away the earth's surface, and this combined work is called denudation.
Read the full explanation →The activities or services focussed on creation, rearrangement and interpretation of new and existing ideas are referred to as
- A.quaternary activities
- B.quinary activities
- C.tertiary activities
- D.secondary activities
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Services that create, rearrange and interpret new and existing ideas, interpret data and evaluate new technologies are classed as quinary activities.
Read the full explanation →Consider the following statements :
1. Rocks do not remain in their original form for long and undergo transformation.
2. Transformation of rocks is caused by weathering, erosion and metamorphic action.
Which of the statements given above is/are correct?
- A.1 only
- B.2 only
- C.Both 1 and 2
- D.Neither 1 nor 2
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Rocks are constantly changed from one form to another, and the agents of that change are weathering, erosion and metamorphism, which together make up the rock cycle.
Read the full explanation →Which one of the following is not a mountain peak of the Andaman and Nicobar Islands?
- A.Saddle Peak
- B.Mount Thuillier
- C.Lhotse Peak
- D.Mount Diavolo
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Lhotse is not in the Andaman and Nicobar Islands at all; it is a Himalayan peak on the border of Nepal and Tibet, just south of Mount Everest, and at about 8,516 metres it is the fourth-highest mountain in the world.
Read the full explanation →Which one of the following Indian States has the longest coastline?
- A.Tamil Nadu
- B.Gujarat
- C.Maharashtra
- D.Andhra Pradesh
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Gujarat has the longest coastline of any Indian state. Its coast runs from the Rann of Kachchh in the north, around the Gulf of Kachchh and the Saurashtra (Kathiawar) peninsula, into the Gulf of Khambhat and down to the border with Maharashtra near Daman.
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