Daily Static MCQs Quiz for UPSC, IAS, UPPSC/UPPCS, MPPSC. BPSC, RPSC & All State PSC Exams
Subject : Geography (20 December 2023)
1. Consider the following statements:
1. P-waves or ‘primary waves’ move faster and are the first to arrive at the surface whereas S-waves or secondary waves arrive at the surface with some time lag.
2. P-waves can travel only through solid materials whereas S-waves can travel through gaseous, liquid and solid materials.
3. P-waves are considered to be the most damaging waves.
Which of the above statements is/are correct?
(a) Only one
(b) Only two
(c) All three
(d) None
Answer: (A)
Explanation: Release of energy during earthquake generates waves which are called Earthquake Waves. Earthquake waves are basically of two types — body waves and surface waves.
Body waves: They are generated due to the release of energy at the focus and move in all directions travelling through the body of the earth. Hence, the name body waves. The body waves interact with the surface rocks and generate new set of waves called surface waves.
Surface waves: These waves move along the surface. The velocity of waves changes as they travel through materials with different densities. The denser the material, the higher is the velocity. Their direction also changes as they reflect or refract when coming across materials with different densities.
There are two types of body waves. They are called P and S-waves.
P-waves or ‘primary waves’ move faster and are the first to arrive at the surface. The P-waves are similar to sound waves. They travel through gaseous, liquid and solid materials. P-waves vibrate parallel to the direction of the wave. This exerts pressure on the material in the direction of the propagation. As a result, it creates density differences in the material leading to stretching and squeezing of the material.
S-waves or secondary waves arrive at the surface with some time lag. They can travel only through solid materials. This characteristic of the S-waves is quite important. It has helped scientists to understand the structure of the interior of the earth. The direction of vibrations of S-waves is perpendicular to the wave direction in the vertical plane. Hence, they create troughs and crests in the material through which they pass. Surface waves are considered to be the most damaging waves.
Hence, only statement 1 is correct.
2. Consider the following statements regarding Sunspots:
1. Sunspots are areas that appear dark on the surface of the Sun (photosphere). They appear dark because they are hotter than other parts of the Sun’s surface.
2. They are regions of reduced surface temperature caused by concentrations of magnetic field flux that inhibit convection.
Which of the above statements is/are correct?
(a) 1 only
(b) 2 only
(c) Both 1 and 2
(d) Neither 1 nor 2
Answer: (B)
Explanation: Sunspots (some as large as 50,000 km in diameter) are areas that appear dark on the surface of the Sun (photosphere). They appear dark because they are cooler than other parts of the Sun’s surface. However, the temperature of a sunspot is still very hot —around 6,500 degrees Fahrenheit. They are regions of reduced surface temperature caused by concentrations of magnetic field flux that inhibit convection. Photosphere is a visible surface of the Sun, from which is emitted most of the Sun’s light that reaches Earth directly. They are relatively cool because they form at areas where magnetic fields are particularly strong. These magnetic fields are so strong that they keep some of the heat within the Sun from reaching the surface. Hence, statement 1 is not correct and statement 2 is correct.
3. Consider the following statements regarding Intertropical Convergence Zone (ITCZ):
1. The ITCZ is a zone of convergence at the thermal equator where the trade winds meet.
2. It is a zone where air tends to ascend.
3. It is a low pressure belt and migrates with the changing position of the thermal equator.
How many of the above statements is/are correct?
(a) Only one
(b) Only two
(c) All three
(d) None
Answer: (C)
Explanation: The ITCZ is a zone of convergence at the thermal equator where the trade winds meet and it is a zone where air tends to ascend. It is a low pressure belt and migrates with the changing position of the thermal equator. In July, the ITCZ is located around 20°N-25°N latitudes (over the Gangetic plain), sometimes called the monsoon trough. This monsoon trough encourages the development of thermal low over north and northwest India. Due to the shift of ITCZ, the trade winds of the southern hemisphere cross the equator between 40° and 60°E longitudes and start blowing from southwest to northeast due to the Coriolis force. Hence, statement 2 is correct.
4. The tropical cyclones do not occur close to the equator because of:
(a) Weak coriolis force
(b) Light and variable winds
(c) Excessive humidity
(d) Convective activity
Answer: (A)
Explanation: Tropical cyclones are violent stroms that originate over oceans in tropical areas and move over to the coastal areas bringing about large scale destruction caused by violent winds, very heavy rainfall and storm surges. This is one of the most devastating natural calamaties. Presence of the Coriolis force is one of the important conditions favourable for the formation and intensification of tropical storms. Since, there is weak coriolis force close to equator, then tropical cyclone does not occur close to the equator.
5. It was formed due to Ocean-Continent collision. Average height of this mountain is 4,000 m. It is longest continental mountain range in the world. It is the world's highest mountain range outside of Asia.
The above passage is related to which of the following mountain?
(a) Rocky Mountains
(b) Andes Mountains
(c) Ural Mountains
(d) Appalachian Mountains
Answer: (B)
Explanation: The Andes is the longest continental mountain range in the world. It is formed due to Ocean-Continent collision. The average height of this mountain is 4,000 m. It spreads along Venezuela, Colombia, Ecuador, Peru, Bolivia, Chile, and Argentina. The Andes is the world's highest mountain range outside of Asia. The highest peak, Mount Aconcagua, rises to an elevation of about 6,962 m above sea level. World's highest volcanoes are in the Andes. Ojos del Salado (6,893 m) on the Chile-Argentina border is the highest volcano on earth. Hence, option (b) is correct.
