1113 RAS Prelims practice MCQs on science and technology are on this page, in 6 chapters. They cover the basics of everyday science, computers and information technology, defence and space technology in India, genetics, biotechnology and nanotechnology, science and technology policies and government programmes, and recent advances with Indian contributors and indigenisation. Each question has an answer and an explanation.
Practice questions based on the RPSC RAS Prelims syllabus. They follow the exam pattern but are not past-paper questions.
Showing 751–760 of 1113 questions
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RAS PrelimsScience and Technology · Genetics, Biotechnology and Nanotechnology
Q751. Consider the following statements about nanotechnology: I. Nanomaterials exhibit significantly different physical and chemical properties compared to their bulk counterparts. II. An increase in the surface area-to-volume ratio at the nanoscale often increases chemical reactivity. III. Richard Feynman is widely considered a founding father of nanotechnology concepts. Which of the above statement(s) is/are correct?
Explanation
Nanomaterials possess distinct properties compared to bulk materials due to quantum effects and a drastically increased surface area-to-volume ratio, which often significantly enhances their chemical reactivity. The theoretical foundation for the field was famously laid by physicist Richard Feynman in his 1959 lecture. These three points form the fundamental basis for understanding why nanotechnology is so versatile across diverse disciplines.
RAS PrelimsScience and Technology · Genetics, Biotechnology and Nanotechnology
Q752. A nanometer is equal to:
Explanation
A nanometer is a unit of length in the metric system equal to one-billionth of a meter. In scientific notation, this is expressed as 10 to the power of negative nine meters. To provide perspective, a single human hair is approximately 80,000 to 100,000 nanometers wide. This extreme miniaturization is what allows nanotechnology to interact with biological molecules on their own scale.
RAS PrelimsScience and Technology · Genetics, Biotechnology and Nanotechnology
Q753. Which phenomenon explains why quantum dots emit light of varying colors depending on their size?
Explanation
The unique ability of quantum dots to emit light of specific colors based on their size is a result of a phenomenon called quantum confinement. When a semiconductor crystal becomes smaller than a certain threshold, its electronic properties change. Smaller dots have a larger energy gap and emit shorter wavelengths, while larger dots have a smaller gap and emit longer wavelengths of light.
RAS PrelimsScience and Technology · Genetics, Biotechnology and Nanotechnology
Q754. Which of the following approaches involves assembling atoms or molecules to build nanoscale structures?
Explanation
In nanotechnology, the bottom-up approach refers to the process of building complex nanoscale structures by assembling them atom-by-atom or molecule-by-molecule. This is often achieved through chemical synthesis or self-assembly, where molecules naturally organize themselves into stable structures due to their inherent chemical properties.
RAS PrelimsScience and Technology · Genetics, Biotechnology and Nanotechnology
Q755. Identify the incorrect statement regarding nanomaterials.
Explanation
Carbon nanotubes are actually exceptional conductors of electricity, far superior to wood and even better than some metals like copper. They have the ability to carry high electrical currents with very little resistance. Other statements are correct: gold nanoparticles can appear red or purple; breaking down bulk materials increases their relative surface area; and graphene is famously the thinnest known material.
RAS PrelimsScience and Technology · Genetics, Biotechnology and Nanotechnology
Q756. The scanning tunneling microscope (STM) and atomic force microscope (AFM) are essential tools in nanotechnology because they allow scientists to:
Explanation
Standard optical microscopes cannot see objects at the nanoscale because they are limited by the wavelength of light. The scanning tunneling microscope and atomic force microscope are revolutionary tools that use physical probes to map the surface of materials at the atomic level. These instruments not only allow scientists to visualize individual atoms but also enable them to physically move and manipulate them.
RAS PrelimsScience and Technology · Genetics, Biotechnology and Nanotechnology
Q757. The famous 1959 lecture "There’s Plenty of Room at the Bottom", which conceptually launched nanotechnology, was given by:
Explanation
Richard Feynman gave the 1959 lecture There’s Plenty of Room at the Bottom, which is seen as the conceptual start of nanotechnology.
RAS PrelimsScience and Technology · Genetics, Biotechnology and Nanotechnology
Q758. Consider the following statements regarding applications of nanotechnology in medicine (nanomedicine): I. Nanoparticles can be engineered for targeted drug delivery to cancer cells, minimizing damage to healthy cells. II. Magnetic nanoparticles are used as contrast agents to enhance MRI imaging. III. Nanoshells can be injected into tumors and heated using infrared light to destroy cancer cells. IV. Nanorobots are currently widely used in hospitals to perform complex open-heart surgeries independently. Which of the above statement(s) is/are correct?
Explanation
Nanomedicine utilizes nanoparticles for targeted drug delivery to tumors and uses magnetic particles as contrast agents to improve MRI scans. Nanoshells are also used in photothermal therapy to selectively heat and kill cancer cells. However, nanorobots capable of performing independent surgeries are still largely in the theoretical stages and are certainly not yet widely used in hospitals for complex operations.
RAS PrelimsScience and Technology · Genetics, Biotechnology and Nanotechnology
Q759. Consider the following statements about nanotechnology applications: I. Zinc oxide and titanium dioxide nanoparticles are used in sunscreens because they absorb UV light and are transparent on the skin. II. Silver nanoparticles are integrated into wound dressings and fabrics for their strong antimicrobial properties. III. Nanofilters can remove viruses and heavy metal ions from contaminated water. IV. Quantum dots are used in modern displays (QLED TVs) for brighter and more accurate colors. V. Nanomaterials are unable to store hydrogen for clean energy applications. Which of the above statement(s) is/are correct?
Explanation
Nanotechnology has widespread applications: nanoparticles in sunscreens provide UV protection; silver nanoparticles serve as potent antimicrobials; nanofilters are used for water purification; and quantum dots enhance modern QLED displays. However, certain nanomaterials, such as carbon nanotubes and metal-organic frameworks, are actually being extensively researched for their high efficiency in safely storing hydrogen for clean energy vehicles and power systems.
RAS PrelimsScience and Technology · Genetics, Biotechnology and Nanotechnology
Q760. In the field of electronics, the integration of nanotechnology allows for:
Explanation
Moores Law is the observation that the number of transistors on a microchip doubles approximately every two years. To maintain this pace, transistors must become smaller and smaller. Nanotechnology allows engineers to design and manufacture transistors at the scale of just a few nanometers. This extreme miniaturization is essential for creating faster, more powerful, and more energy-efficient computers and electronic devices.
Answer key for these questions
Q
Correct answer
751
(d) I, II and III
752
(b) 10-9 meters
753
(c) Quantum confinement
754
(a) Bottom-up approach
755
(d) Carbon nanotubes are poorer conductors of electricity than wood.
756
(b) Observe and manipulate individual atoms and molecules
757
(a) Richard Feynman
758
(c) I, II and III
759
(a) I, II, III and IV
760
(b) Moore’s law to continue by miniaturizing transistors to the nanoscale
Key facts from Science and Technology
The RPSC paper is General Knowledge and General Science, so science questions come with a strong dose of applied and recent topics.
Everyday science questions test the laws and terms of physics, chemistry and biology through examples.
Defence and space questions pair a missile, satellite or mission with its year and organisation.
Policy questions ask for the year, the body and the aim of schemes like STIP, the National Quantum Mission and BioE3.
Health, environment and agriculture are on a separate page, with their own chapters.
Frequently asked questions
How many RAS Prelims practice MCQs are there on Science and Technology?
This page has 1113 practice MCQs on Science and Technology. Each has the correct answer, and most have an explanation.
Which chapters does the science and technology set cover?
Six chapters: basics of everyday science; computers, information and communication technology; defence and space technology in India; genetics, biotechnology and nanotechnology; science and technology policies and government programmes; and recent advances, Indian contributors and indigenisation.
Is science and technology part of the RAS Prelims syllabus?
Yes. The RPSC paper is called General Knowledge and General Science, and its syllabus lists science and technology topics along with environment, health, agriculture and government programmes, so questions can come from any of these areas.
How should I prepare science for RAS Prelims?
Revise the concepts by examples, then learn the missions, schemes and scientists with their year and organisation. Attempt each chapter, read the explanations and keep a list of the facts you missed.
