UPSC 2009 Science and Technology Questions with Answers

Explanation

WiMAX (WIMAX forum was formed in June 2001 to promote conformity and interoperability) is a communication technology that provides high-speed wireless broadband internet access. It is designed to offer both fixed and mobile broadband services over long distances, often as a replacement or supplement to traditional wired broadband technologies like digital subscriber line (DSL) or cable. Broadband Internet Access, Wireless Backhaul (for wireless link between a cellular base station and the core network) and Mobile Broadband etc. are based on WiMAX technology. It provides high-speed internet access, bridging the connectivity gap for both urban and rural areas, especially in the last-mile segment.

Explanation

The Shourya is a canisterised missile system that can be easily handled, transported and stored within the canister for longer shelf-life. The high manoeuvrability of the missile makes it less vulnerable to available anti-missile defence systems.

Statement 1 is incorrect: The Can carry a payload of 200 to 1000 kg.Propellant - Solid fuel is a hypersonic surface-to-surface tactical missile. It is known to travel at speeds of up to Mach 7.5, which is slightly less than Mach 8.

Statement 2 is incorrect: The range of the Shourya missile is approximately 750-1900 km, depending on its payload, but its operational range typically does not exceed 1600 km in standard configurations.

Explanation

Statement 1 is incorrect: INS Sindhughosh is not an aircraft carrier. It is a diesel-electric submarine of the Sindhughosh class, which is based on the Russian Kilo-class submarines. It is used for anti-submarine warfare, reconnaissance, and intelligence gathering.

Statement 2 is incorrect: INS Viraat is not a submarine. It was an aircraft carrier and served as the flagship of the Indian Navy for many years. It played a significant role in enhancing India’s naval power before being decommissioned in 2017.

Explanation

Sub-atomic particles are particles that are smaller than an atom. They are the basic building blocks of atoms. They are primarily categorized into two groups: elementary particles which are indivisible, and composite particles which are combinations of elementary particles.

Option (b) is correct: In the year 2008, the organization that conducted a complex scientific experiment in which sub-atomic particles were accelerated to nearly the speed of light was the European Organization for Nuclear Research (CERN). CERN operates the Large Hadron Collider (LHC), where particles are accelerated to extremely high speeds to explore fundamental physics. The experiment helps in understanding the Standard Model of Particle Physics exploring dark matter and studying the properties of fundamental forces.

Explanation

Option (c) is correct: Night vision apparatus detects infrared waves emitted by objects as heat. Warmer objects emit more infrared radiation which is invisible to the human eye but can be captured and converted into a visible image by night vision devices. Infrared waves are electromagnetic waves with wavelengths longer than visible light but shorter than microwaves, typically used in thermal imaging, night vision, and remote sensing. Options (a) and (b) are incorrect: Microwaves are used in cooking and radar systems and radio waves are used for communication in broadcasting, mobile phones, and satellite transmissions.

Explanation

Ammonium chloride (NH₄Cl) is a primary component of the electrolyte paste used in dry cells. Zinc chloride (ZnCl₂) serves as the negative electrolyte, and it is often mixed with ammonium chloride in a paste to form the electrolyte for the dry cell. These components, along with a zinc anode and a carbon cathode, are commonly used in the construction of dry cells, which power small devices such as flashlights and radios.

Explanation

Option (d) is correct: Nitroglycerine is a highly explosive compound, commonly used in the production of dynamite. It is a liquid with high sensitivity to shock and heat, making it a powerful and widely used explosive in mining and demolition. Options (a), (b) and (c) are incorrect:

Phosphorus Trichloride is a chemical used in the manufacture of pesticides, not an explosive. Mercuric Oxide is an oxidizing agent used in batteries and chemical synthesis, not explosive. Graphite is a form of carbon used in lubricants and as an electrode material, not an explosive.

Explanation

Saffron spice is made from the stigma of the Crocus sativus flower, commonly known as the saffron crocus. The stigmas are handpicked, dried, and processed to produce saffron. Each flower has only three stigmas, making the harvesting process labor-intensive and contributing to saffron’s high value. The stigmas are highly prized for their distinctive flavor, aroma, and vibrant golden color.

Explanation

Statement 1 is correct: The sweet orange plant is propagated through the grafting technique where a scion (shoot) from a desired sweet orange tree is grafted onto the rootstock of a compatible plant. This ensures the plant retains the desired traits such as high fruit quality and disease resistance.

Statement 2 is correct: The jasmine plant is commonly propagated by layering technique, particularly mound layering or air layering. This method involves bending a healthy branch to the ground or wrapping it with moist materials to encourage root development, which helps maintain the plant’s genetic identity and growth potential.

Explanation

Genetic disorders are caused by abnormalities in an individual’s DNA, inherited from parents or arising from mutations. They can affect structure, function, or production of proteins. Types include single-gene disorders (e.g., cystic fibrosis), chromosomal disorders (e.g., Down syndrome), and multifactorial disorders (e.g., diabetes), impacting health, development, or metabolism.

Option (d) is correct:

Color blindness is a sex-linked recessive disorder carried on the X chromosome. In the above case, the woman suffers from color blindness but her husband does not. Woman’s Genotype: Since the woman has color blindness, her genotype must be X^cX^c (as both X chromosomes carry the color blindness allele). Man’s Genotype: Since the man does not have color blindness, his genotype must be XY (as the Y chromosome does not carry the color blindness gene). Children’s Genotypes:

Son: A son inherits his X chromosome from his mother and his Y chromosome from his father. Since the mother has the X^c chromosome, the son’s genotype will be X^cY, meaning the son will suffer from color blindness. Daughter: A daughter inherits one X chromosome from her mother and one X chromosome from her father. Since the father has a normal X chromosome, the daughter’s genotype will be X^cX. Since color blindness is a recessive trait, the daughter will be a carrier but won’t suffer from color blindness.