Solution (c)

Explanation:

• Our Solar system consists of eight planets. Out of the eight planets, mercury, venus, earth and mars are called as the inner planets as they lie between the sun and the belt of asteroids the other four planets are called the outer planets. They are also called Terrestrial, meaning earth-like as they are made up of rock and metals, and have relatively high densities. Hence, statement 1 is correct.
• The rest four planets (Jupiter, Saturn, Neptune and Uranus) are called Jovian or Gas Giant planets. Jovian means Jupiter-like. Most of them are much larger than the terrestrial planets and have thick atmosphere, mostly of helium and hydrogen. All the planets were formed in the same period sometime about 4.6 billion years ago. Hence, statement 2 is not correct.

Solution (d)

Explanation:

• The solar output received at the top of the atmosphere varies slightly in a year due to the variations in the distance between the earth and the sun. During its revolution around the sun, when the earth is farthest from the sun, it is called aphelion. Hence, statement 1 is not correct.
• The earth is farthest from the sun (152 million km) on 4th July. On 3rd January, the earth is the nearest to the sun (147 million km). This position is called perihelion. Hence, statement 2 is not correct.
• The annual insolation received by the earth on 3rd January is slightly more than the amount received on 4th July. However, the effect of this variation in the solar output is masked by other factors like the distribution of land and sea and the atmospheric circulation. Hence, this variation in the solar output does not have great effect on daily weather changes on the surface of the earth. Hence, statement 3 is not correct.

Solution (b)

Explanation:

• Solar constant is the total radiation energy received from the Sun per unit of time per unit of area. It is most accurately measured from satellites where atmospheric effects are absent. The value of the constant is approximately 1.366 kilowatts per square metre. Hence, statement 1 is correct.
• The insolation received at the surface varies from about 320 Watt/m2 in the tropics to about 70 Watt/m2 in the poles. Maximum insolation is received over the subtropical deserts, where the cloudiness is the least. Hence, statement 2 is not correct.
• Equator receives comparatively less insolation than the tropics. Generally, at the same latitude the insolation is more over the continent than over the oceans. In winter, the middle and higher latitudes receive less radiation than in summer. Hence, statement 3 is not correct.

Solution (a)

Explanation:

• The early atmosphere largely contained water vapour, nitrogen, carbon dioxide, methane, ammonia and very little of free oxygen. The process through which the gases were outpoured from the interior is called degassing. Continuous volcanic eruptions contributed water vapour and gases to the atmosphere. As the earth cooled, the water vapour released started getting condensed. Hence, statement 1 is correct.
• The present composition of earth’s atmosphere is chiefly contributed by nitrogen and oxygen. It is composed of nitrogen (78%), oxygen (21%), argon (0.9%), carbon dioxide (0.04%) and various trace gases. A variable amount of water vapour is also present in the atmosphere (approx. 1% at sea level) and it decreases with altitude. Hence, statement 2 is not correct.

Solution (d)

Explanation:

• The Paleogene period is divided into–from oldest to youngest–the Paleocene, Eocene, and Oligocene epochs. The Neogene is divided into the Miocene and Pliocene epochs. Finally, the Quaternary is divided into the Pleistocene and Holocene epochs. Hence, option d is the correct answer.

Solution (b)

Explanation:

• Analysis of properties of matter indirectly provides information about the interior. Some of the indirect sources to know about the interior of the earth include gravitation, magnetic field, and seismic activity. Surface rocks or the rocks we get from mining areas are examples of direct sources. Hence, option b is the correct answer.

Solution (c)

Explanation:

• An earthquake in simple words is shaking of the earth. It is a natural event. It is caused due to release of energy, which generates waves that travel in all directions. All natural earthquakes take place in the lithosphere. Hence, statement 1 is correct.
• Lithosphere refers to the portion of depth up to 200 km from the surface of the earth. It includes the brittle upper portion of the mantle and the crust, the outermost layers of Earth’s structure. It is bounded by the atmosphere above and the asthenosphere (another part of the upper mantle) below. Hence, statement 2 is correct.

Solution (b)

Explanation:

• Earthquake waves are basically of two types- body waves and surface waves. There are two types of body waves. They are called P and S-waves. P-waves move faster and are the first to arrive at the surface and are also called ‘primary waves.’ The surface waves are the last to report on seismograph and are more destructive. Hence, statement 1 is correct.
• The P-waves are similar to sound waves. They leave behind a trail of compressions and rarefactions on the medium they move through. P waves are also called pressure waves for this reason. Certain animals, such as dogs, can feel the P waves much before an earthquake hits the crust. Hence, statement 2 is correct.
• They travel through gaseous, liquid and solid materials. On the other hand, S-waves can travel only through solid materials. This characteristic of the S-waves is quite important and it has helped scientists to understand the structure of the interior of the earth. Hence, statement 3 is not correct.

Solution (a)

Explanation:

• The earthquake events are scaled either according to the magnitude or intensity of the shock. The magnitude scale is known as the Richter scale, while the intensity scale is named after Mercalli, an Italian seismologist. The intensity scale takes into account the visible damage caused by the event. Hence, statement 1 is correct.
• The Richter scale range measures earthquakes from a magnitude of 1 (smallest) to a magnitude of 10 (largest). It is a base-10 logarithmic scale, meaning that each order of magnitude is 10 times more intensive than the last one. The range of Mercalli scale or intensity scale is from 1-12. Hence, statement 2 is not correct.

Solution (a)

Explanation:

• Earth has three layers: the crust, the mantle, and the core. It is the outermost solid part of the earth. It is brittle in nature and is made of solid rocks and minerals. Beneath the crust is the mantle, which is also mostly solid rocks and minerals, but punctuated by malleable areas of semi-solid magma. At the centre of Earth is a hot, dense metal core. Hence, statement 1 is correct.
• The thickness of the crust varies under the oceanic and continental areas. Oceanic crust is thinner as compared to the continental crust. The mean thickness of oceanic crust is 5 km whereas that of the continental is around 30 km. The continental crust is thicker in the areas of major mountain systems. It is as much as 70 km thick in the Himalayan region. Hence, statement 2 is correct.
• The portion of the interior beyond the crust is called the mantle. The mantle extends from Moho’s discontinuity to a depth of 2,900 km. The upper portion of the mantle is called asthenosphere. Hence, statement 3 is not correct.

Solution (b)

Explanation:

• Batholith is a large body of magmatic material that cools in the deeper depth of the crust develops in the form of large domes. They appear on the surface only after the denudational processes remove the overlying materials. They cover large areas, and at times, assume depth that may be several km. These are granitic bodies. Batholiths are the cooled portion of magma chambers. Hence, option b is the correct answer.

Consider the following statements:

1. These are the most explosive volcanoes on the earth’s surface.
2. The Hawaiian volcanoes are the most famous examples of shield volcanoes.
3. The shield volcanoes are mostly made up of basalt, and thus are not very steep.

Which of the above statements are correct?

Solution (d):

Explanation:

• About 98% of the total crust of the earth is composed of eight elements like oxygen, silicon, aluminium, iron, calcium, sodium, potassium and magnesium in the descending order and the rest is constituted by titanium, hydrogen, phosphorous, manganese, sulphur, carbon, nickel and other elements. Hence, option d is the correct answer.

Solution (c)

Explanation:

• Quartz is one of the most important components of sand and granite. It consists of silica. It is the second most abundant mineral in Earth’s crust after feldspar. It occurs in nearly all acid igneous, metamorphic, and sedimentary rocks. Hence, statement 1 is correct.
• It is a hard mineral virtually insoluble in water. It is highly resistant to weathering and tends to concentrate in sandstones and other detrital rocks. It is an essential mineral in such silica-rich felsic rocks as granites, granodiorites, and rhyolites. Hence, statement 2 is not correct.
• It is white or colourless and used in radio and radar. It is one of the most important components of granite. China, Japan, and Russia are the world’s primary producers of quartz. Hence, statement 3 is correct.

Solution (a)

Explanation:

• The word metamorphic means ‘change of form’. These rocks form under the action of pressure, volume and temperature (PVT) changes. Metamorphism occurs when rocks are forced down to lower levels by tectonic processes or when molten magma rising through the crust comes in contact with the crustal rocks or the underlying rocks are subjected to great amounts of pressure by overlying rocks. Hence, statement 1 is correct.
• Sandstone, conglomerate, limestone, shale, loess etc. are examples of sedimentary rocks. Gneissoid, granite, syenite, slate, schist, marble, quartzite etc. are some examples of metamorphic rocks. Hence, statement 2 is not correct.

Solution (c)

Explanation:

• The innermost layer surrounding the earth’s centre is called the core, which is about 3500 km in radius.
• Core is the most dense layer of the earth with its density range from 9.5 to 14.5 and sometimes even higher. It is composed mainly of iron and nickel thus commonly known as Nife. Hence statement 1 is correct.
• The core consists of two sub-layers. The inner one is solid and the outer one is semi-liquid.
• The mantle contains more iron and magnesium compared to the crust.
• The mantle is denser than the crust because the temperature and pressure inside the Earth increase with depth. Hence statement 2 is incorrect.
• Earth comprises four primary layers such as an inner core at the planet’s centre, surrounded by the outer core, mantle, and crust.
• The formation of a new enigmatic layer called the E prime layer at the outermost part of Earth’s core is a result of surface water penetrating deep into the planet, altering the composition of the metallic liquid core’s outermost region. Hence statement 3 is correct.

Solution (a)

Explanation:

• Sedimentary rocks formed as a result of the deposition of the insoluble mechanically transported material in the form of bedded deposits, sheets, and layers of various sizes.
• Sedimentary rocks are generally layered rocks because of the deposition of similar or dissimilar in colour, grain size, or mineral composition, sediments one over another in a basin. These deposits through compaction turn into rocks. This process is called lithification.
• In many sedimentary rocks, the layers of deposits retain their characteristics even after lithification. Hence, a number of layers of varying thickness are witnessed in the sedimentary rocks. Hence statement 1 is correct.
• The individual rock particles are first broken from rocks and then transported by running water, ocean currents, glaciers, or even by wind from one place to another.
• The process by which rock-forming material is laid down is called sedimentation or deposition. It may settle in calmer waters of lakes or oceans or at places where the transporting agent has no longer enough energy to carry them farther. These are identified as riverine, lacustrine (formed by the lake), glacial, or aeolian (formed by wind) sedimentary rocks regarding their deposition near rivers, lakes, glaciers, or deserts respectively. Therefore, Lacustrine sedimentary rocks are not formed by wind in desert areas. Hence statement 2 is incorrect.

Solution (d)

Explanation:

 Terrestrial planets are planets that are made up of mostly rock and metal and have a solid, rocky surface. They are also known as inner planets or rocky planets. The four terrestrial planets in our solar system are Mercury, Venus, Earth, and Mars. These planets are also the four innermost planets in the solar system. Hence option d is correct.

Solution (d)

Explanation:

There are two types of seismic waves: Body waves and Surface waves.

There are two types of Body Waves. They are called P and S-waves.

P-waves move faster and are the first to arrive at the surface. These are also called primary waves. The P waves are similar to sound waves. They travel through gaseous, liquid, and solid materials.

Secondary waves arrive at the surface with some time lag. These are called secondary waves. They can travel only through solid materials. Secondary (S) waves are known as transverse waves. These waves travel at right angles to the direction of the wave propagation. These waves seem to be like light waves. Secondary (S) waves travel only through the solid state of matter. An increase in the density of rocks increases the velocity of the waves and vice versa. The velocity of S waves varies from 3.25 km per second at or near the surface to 7.0 km per second in the interior. Hence option d is correct

Solution (d)

Hoyle’s concept of a steady state considered the universe to be roughly the same at any point in time. However, with greater evidence becoming available about the expanding universe, the scientific community at present favours the argument of expanding the universe.

Steady-state theory in cosmology was developed in 1948 as an alternative to the Big Bang theory.  The main assumptions of the steady-state theory:

• The universe has existed forever and will exist forever.
• Matter is continuously created to fill in space created by the expansion.
• The universe appears basically the same at all places and at all times.
• The universe is in a state of dynamic equilibrium.
• The expansion of the universe is smooth and constant.

Hence option d is correct.

Solution (c)

Statement Analysis:

Context: The Indian garment sector expects short-term gains due to the Bangladesh crisis.

• The Cotton Textiles Export Promotion Council was the first council set up after Independence by the Government of India in 1954. Hence statement 1 is correct.
• It is an autonomous, non-profit body dedicated to the promotion of exports.
• It is popularly known as TEXPROCIL has been the international face of cotton textiles from India facilitating exports worldwide.
• It has a membership of around 3,000 companies spread across major textile clusters in India. Hence statement 2 is correct.
• Its members are well-established manufacturers and exporters of cotton textile products like Cotton, Yarns, Fabrics, and Home Textiles, showcasing a dazzling array of products across the value chain.
• It connects international buyers with appropriate suppliers and facilitates interaction that enables them to source their specific needs.
• It promotes exports of raw cotton, cotton yarns, woven and knitted fabrics, home textiles, and technical textiles. Hence statement 3 is correct.

Source: https://www.thehindu.com/business/indian-garment-sector-expects-short-term-gains-due-to-bangladesh-crisis/article68493026.ece

Solution (b)

Statement Analysis:

Context: Wayanad is ranked 13th, while Thrissur, Palakkad, Malappuram, and Kozhikode are ranked third, fifth, seventh, and 10th, respectively, in the Landslide Atlas of India.

• The Landslide Atlas of India has assessed and ranked 147 landslide-prone districts in 147 districts in 17 States and two Union Territories. Hence statement 1 is incorrect.
• Its database covers landslide-vulnerable regions of India in the Himalayas and Western Ghats.
• It is prepared by the National Remote Sensing Centre, one of the centres of the Indian Space Research Organisation. Hence statement 2 is correct.
• Satellite data of high to very high-resolution nature were extracted from IRS-1D PAN+LISS-III, Resourcesat-1, 2 and 2A LISS-IV Mx, Cartosat-1 and 2S, and aerial images were used in the mapping of landslides.
• Rudraprayag in Uttaranchal was ranked first in the landslide atlas. Hence statement 3 is correct.

Source: https://www.thehindu.com/news/national/kerala/wayanad-was-among-kerala-districts-that-ranked-high-on-isro-landslide-atlas/article68467556.ece

Solution (c)

Statement Analysis:

Context: IAF’s largest multilateral exercise Tarang Shakti to see the participation of over 150 aircraft.

• The Exercise Tarang Shakti will be the largest international air exercise ever conducted in India. Hence statement 1 is correct.
• Phase one of the exercise will be conducted at Sulur in Tamil Nadu from August 6 to August 14 and four countries including France, Germany, Spain, and the United Kingdom will participate with their assets.
• Phase two will be held at Jodhpur in Rajasthan from September 1 to 14 and it will see participation from Australia, Bangladesh, Greece, Singapore, UAE, and the USA with their assets.
• It aims to strengthen strategic relations with our friends from the international community. Hence statement 2 is correct.

Source: https://www.thehindu.com/news/national/iafs-largest-multilateral-exercise-tarang-shakti-to-see-participation-of-over-150-aircraft/article68469453.ece#:~:text=The%20Indian%20Air%20Force%20is,skies%20over%20Sulur%20and%20Jodhpur

Solution (a)

Statement Analysis:

Context: Preeti Sudan was appointed chairperson of the Union Public Service Commission (UPSC) after Manoj Soni resigned from the post.

• The Union Public Service Commission (UPSC) is the central recruiting agency in India. It is an independent constitutional body. The provisions regarding the composition of UPSC, the appointment and removal of its members, and the powers and functions of UPSC are provided in Part XIV of the Indian Constitution under Article 315 to Article 323.
• The Chairman and other members of the UPSC are appointed by the President of India. Hence statement 1 is incorrect.
• Any person who has once held the office as a member of a Public Service Commission is ineligible for reappointment to that office.
• Any member of the UPSC shall hold office for a term of six years or till the age of 65 years, whichever is earlier. Hence statement 2 is incorrect.
• The Chairman or any other member of UPSC may be removed if he/she:
• is adjudged an insolvent.
• engages during his/her term of office in any paid employment outside the duties of his/her office.
• is, in the opinion of the President, unfit to continue in office because of infirmity of mind or body.
• The Chairman or any other member of UPSC shall only be removed from his/her office by order of the President of India. Hence statement 3 is incorrect.
• The President can suspend the Chairman or any other member from his/her office in respect of whom a reference has been made to the Supreme Court.
• Only two women have been chairperson of the UPSC since its inception. Ms. Sudan is only the second woman to head the UPSC since R.M. Bathew served as the chairperson from 1992 to 1996. Hence statement 4 is correct.

Source: https://www.thehindu.com/news/national/former-union-health-secretary-preeti-sudan-to-take-charge-as-chairman-of-upsc-on-august-1/article68467375.ece

Solution (d)

Statement Analysis:

Context: With the Vietnamese PM by his side, the Indian PM said India supports development and not expansionism — a thinly disguised reference to Beijing’s belligerence in the Indo-Pacific.

• Vietnam shares land borders with China to the north, and Laos and Cambodia to the west. Hence statement 1 is correct.
• Hanoi is its capital city.
• It shares maritime borders with Thailand, the Philippines, Indonesia, and Malaysia. Hence statement 2 is correct.
• The Gulf of Tokin is a shallow, crescent-shaped body of water located in the northwest part of the South China Sea. It is known as “Beibu Gulf” in Chinese and “Bac Bo Gulf” in Vietnamese.
• It borders the Gulf of Tokin on its northern coast. Hence statement 3 is correct.
• Mekong River and Red River flow through Vietnam. Hence statement 4 is correct.

Source: https://indianexpress.com/article/india/vietnamese-pm-by-his-side-modi-takes-dig-at-china-we-dont-support-expansionism-9490039/

Test explained

Solution (c)

Statement Analysis:

Context: The newly constituted European Commission (EC), the executive arm of the European Union, elected Ursula von der Leyen, the EC’s first female President, for a second term.

• The European Commission (EC) is an executive body of the European Union. Hence statement 1 is correct.
• It operates as a cabinet government, with 27 members of the Commission. There is one member per member state. These members are proposed by member countries and the European Parliament gives final approval to them.
• It is responsible for proposing legislation, implementing decisions, upholding the EU treaties, and managing the day-to-day business of the EU. Hence statement 2 is correct.
• The Commission is divided into departments known as Directorates-General (DGs) that can be likened to departments or ministries headed by a director-general who is responsible to a commissioner High Representative (HR) of the Union for Foreign Affairs and Security Policy is appointed by the European Council by voting and The President of the EC must be in agreement with the decision. HR is charged with shaping and carrying out the EU’s foreign, security, and defence policies.
• Its president is proposed by the European Council.
• The selection of the EC President entails a two-stage process in consonance with the results of the parliamentary polls.
• The candidate is initially proposed and elected by the European Council — comprising the leaders of the EU’s 27 member countries — and subsequently put to a secret ballot in parliament. Hence statement 3 is correct.

Source: https://www.thehindu.com/news/international/election-of-the-european-commission-president-explained/article68474593.ece

Solution (d)

Statement Analysis:

Context: The Central government’s Rs 72,000 crore Great Nicobar Island (GNI) infrastructure has faced legal challenges in the National Green Tribunal (NGT) and the Calcutta High Court, which has jurisdiction over the Andaman and Nicobar Islands. 

Hence option d is correct.

Source: https://indianexpress.com/article/explained/legal-cases-greater-nicobar-infra-project-9490929/

Solution (c)

Statement Analysis:

Context: The Union Home Minister and Minister of Cooperation launched the e-Sakshya, Nyaya Setu, Nyaya Shruti, and e-Summon apps for the three new criminal laws in Chandigarh. 

• Nyaya Shruti is an automated system that facilitates court hearings through electronic media.
• It streamlines court hearings via video conferencing, sending alerts and links to police, prisons, prosecution, and forensics whenever summons or warrants are issued. Hence statement 1 is correct.
• Nyaya Setu provides a unified legal interface for legal information, legal advice, and legal assistance.
• It enables a more inclusive and just society.
• It is connected with the police, prisons, prosecution, forensics, and designated access points. Whenever the court issues a summons or warrant, an alert is sent to the domain application, and a video conferencing link for judicial hearings is provided to all relevant individuals and officers. Hence statement 2 is correct.

Note:

• The e-Sakshya app enables officers to capture and transmit crime scene evidence, witness information, and photos/videos securely to an evidence locker, linking it to the charge sheet for electronic access by the court.
• e-Summons electronically transmits court orders like summons and warrants to the police, who then receive and deliver them via their mobile devices.

Source: https://www.thehindu.com/news/national/other-states/new-criminal-laws-biggest-reform-of-century-amit-shah/article68485457.ece

Solution (b)

Statement Analysis:

Context:

• The National Multidimensional Poverty is developed by the National Institution for Transforming India (NITI Aayog). Hence option b is correct.
• It measures simultaneous deprivations across three equally weighted dimensions of Health, Education, and Standard of Living that are represented by 12 Sustainable Development Goals-aligned indicators.

Solution (a)

Explanation:

Assumption 1 is correct: The given assumption is based on the lines “IoT security is vital for enterprises, as it includes a wide range of techniques, strategies, protocols, and actions that aim to mitigate the increasing IoT vulnerabilities of modern businesses.” These lines show that if IoT is not secured then it may make modern businesses vulnerable to cyber-attacks which can have serious economic implications. Hence, this assumption is correct as per the passage.

Assumption 2 is incorrect: The given assumption is based on the lines “Due to the unconventional manufacturing of IoT devices and the vast amount of data they handle, there’s a constant threat of cyber-attacks.” These lines show that IoT is under constant threat due to unconventional manufacturing of IOT devices, and the huge data they handle. This does not mean that their data handling capacities are not good. So, to assume that enhancing data handling capacities is a way to secure IoTs is not correct as per the passage.

Solution (d)

Explanation:

Initial speed of train = 63 km/hr

Time taken = 100 minutes

As we know that Distance = speed × time

Distance = 63 × 100/60 = 105 km.

It is given that the new time will be 80 minutes.  So, required speed = 105 /(80/60)  = 78.75 km/hr Hence, option (d) is the right answer.

Alternate Method:

As distance is constant, speed should increase in the same proportion as the time is getting reduced. As the time is getting reduced from 100 minutes to 80 minutes, i.e. a reduction of 20%, the speed must increase by 25%.

So new speed = 125% of 63 km/hr = 78.75 km/hr Hence, option (d) is the right answer.

Solution (d)

Explanation:

Total number of flashlights = 20

Number of defective flashlight = 20 × (2/5) = 8

Number of working flashlights = 20 – 8 = 12

Three flashlights can be selected from 20 flashlights in ²⁰C₃ ways.

Number of ways of drawing 3 flashlights from 8 defective flashlights is ⁸C₃.

So, the probability that all the three flashlights are defective = ⁸C₃/²⁰C₃ = [8!/{3!(8 – 3)!}] / [20!/{3!(20 – 3)!}] = 14/285

The probability that at least one flash light is good = 1 – Probability that no flashlight is good = 1– (14/285) = 271/285

Hence, option (d) is the right answer.

Solution (a)

Explanation:

5400 = 2³x3³x5²; 9000 = 2³x3²x5³

HCF of 5400 and 9000 = 2³x3²x5²

Number of factors of 5400 = (3+ 1) (3+ 1) (2+ 1) = 4x4x3 = 48.

Total number of factors of a^xX b^y X c^z= (x+1) (y+1) (z+1).

Here a, b and c should be prime numbers

Similarly, number of factors of9000 = (3+ 1) (2+ 1) (3+1) = 4x3x4 = 48.

Number of factors of HCF of the two numbers= (3+ 1) (2+ 1) (2+1) = 4x3x3 = 36. Hence, the required number of divisors= (48 + 48) – 2x 36 = 96 – 72 = 24.

Hence, option (a) is the right answer.

Solution (a)

Explanation:

At the beginning, both the boys walk away from each other. After one hour, first boy reaches home and his distance from school is 5 km. This distance does not change after 2 pm.

The second boy walks at the speed of 6 km per hour for the entire 1 hour 10 min.

Distance covered by second boy in 1 hour 10 min = 7 km.

So, Total distance between the boys at 2:10 pm = 7 + 5 = 12 km.  So, option (a) is the right answer.