Science & Technology questions asked in previous year papers of SSC, Banking, Railway and other exams, with the exam and year, answers and explanations.
128 previous-year questions
The Pragyan rover installed in Chandrayaan-2 mission had how many wheels?
Pragyan was a six-wheeled rover carried inside the Vikram lander. Chandrayaan-2 was launched on 22 July 2019 by the GSLV Mk III with an orbiter, the Vikram lander and the Pragyan rover.
Read the full explanation →According to India's National Policy on Biofuels, which of the following can be used as raw materials for the production of biofuels ? 1. Cassava 2. Damaged wheat grains 3. Groundnut seeds 4. Horse gram 5. Rotten potatoes 6. Sugar beet Select the correct answer using the code given below:
The policy allows cassava, damaged wheat, rotten potatoes and sugar beet, but not groundnut seeds or horse gram. The National Policy on Biofuels, 2018 widened the raw materials for ethanol beyond sugarcane molasses.
Read the full explanation →Consider the following statements : 1. Genetic changes can be introduced in the cells that produce eggs or sperms of a prospective parent. 2. A person's genome can be edited before birth at the early embryonic stage. 3. Human induced pluripotent stem cells can be injected into the embryo of a pig. Which of the statements given above is/are correct?
With today's gene-editing and stem cell tools, all three procedures are technically possible. Changes made in germline cells, the cells that give rise to eggs or sperm, are passed on to the next generation, and tools such as CRISPR-Cas9 can make such edits.
Read the full explanation →"The experiment will employ a trio of spacecraft flying in formation in the shape of an equilateral triangle that has sides one million kilometres long, with lasers shining between the craft." The experiment in question refers to
eLISA is the planned space observatory of three spacecraft, linked by lasers in a giant triangle, that will detect gravitational waves.
Read the full explanation →Consider the following activities : 1. Spraying pesticides on a crop field 2. Inspecting the craters of active volcanoes 3. Collecting breath samples from spouting whales for DNA analysis At the present level of technology, which of the above activities can be successfully carried out by using drones ?
Drones are already used for all three jobs: spraying crops, looking into volcanic craters and catching whale breath for study.
Read the full explanation →With reference to "Blockchain Technology", consider the following statements :
1. It is a public ledger that everyone can inspect, but which no single user controls.
2. The structure and design of blockchain is such that all the data in it are about cryptocurrency only.
3. Applications that depend on basic features of blockchain can be developed without anybody's permission.
Which of the statements given above is/are correct?
A blockchain is an open, shared ledger that no single party controls, and anyone can build on a public blockchain without asking permission.
Read the full explanation →With reference to Visible Light Communication (VLC) technology, which of the following statements are correct ?
1. VLC uses electromagnetic spectrum wavelengths 375 to 780 nm.
2. VLC is known as long-range optical wireless communication.
3. VLC can transmit large amounts of data faster than Bluetooth.
4. VLC has no electromagnetic interference.
Select the correct answer using the code given below:
VLC sends data with visible light, which is fast and free of radio interference, but it works only over short distances.
Read the full explanation →In the context of recent advances in human reproductive technology, "Pronuclear Transfer" is used for
Pronuclear transfer is a mitochondrial replacement technique that stops a mother from passing faulty mitochondria to her child. Mitochondria have their own small DNA, inherited only from the mother; defects in it cause serious muscle, heart and brain diseases.
Read the full explanation →A technology for the application of mechanical, electronics, and computer-based systems to control and operate the systems is called.
Automation is the technology in which mechanical parts, electronics and computer based control are put together so that a process is controlled and operated with little human help, which is exactly the description in the question.
Read the full explanation →Name the scientific principle behind the working of optical fibres.
In an optical fibre the glass core has a higher refractive index than the cladding around it, so light that meets the core-cladding boundary at an angle greater than the critical angle is reflected entirely back into the core instead of passing out, and it travels along the fibre in…
Read the full explanation →Which of the following is a multi-barrel rocket system developed by DRDO?
Pinaka is the multi-barrel rocket launcher built for the Indian Army by DRDO's Armament Research and Development Establishment, Pune, and named after the bow of Lord Shiva.
Read the full explanation →Which organization developed Indian robot named "Vyommitra" ?
Vyommitra is a half-humanoid robot built by the Indian Space Research Organisation and shown to the public in January 2020.
Read the full explanation →Which one of the following is the name given to the lander of Chandrayaan-2 ?
The lander of Chandrayaan-2 was named Vikram after Vikram Sarabhai, the father of India's space programme. Chandrayaan-2 was launched by ISRO on 22 July 2019 on a GSLV Mk III rocket from Sriharikota.
Read the full explanation →What is Cas9 protein that is often mentioned in news?
Cas9 is the enzyme in the CRISPR-Cas9 system that cuts DNA at a chosen spot, which is why it is called molecular scissors.
Read the full explanation →Recently, scientists observed the merger of giant 'blackholes' billions of light-years away from the Earth. What is the significance of this observation?
The merger of two black holes sent out ripples in space-time, and catching those ripples was the first direct detection of gravitational waves.
Read the full explanation →RNA interference (RNAi) technology has gained popularity in the last few years. Why?
1. It is used in developing gene silencing therapies.
2. It can be used in developing therapies for the treatment of cancer.
3. It can be used to develop hormone replacement therapies.
4. It can be used to produce crop plants that are resistant to viral pathogens.
Select the correct answer using the code given below.
RNA interference switches particular genes off, and every use in statements 1, 2 and 4 depends on switching a gene off.
Read the full explanation →Which one of the following is the name given by Indian Railways to the indigenously manufactured Train 18?
Train 18, India's first indigenous semi-high-speed train set, was named Vande Bharat Express in January 2019. Train 18 was designed and built by the Integral Coach Factory in Chennai and got its name because it was planned for 2018.
Read the full explanation →In the context of proposals to the use of hydrogen-enriched CNG (H-CNG) as fuel for buses in public transport, consider the following statements :
1. The main advantage of the use of H-CNG is the elimination of carbon monoxide emissions.
2. H-CNG as fuel reduces carbon dioxide and hydrocarbon emissions.
3. Hydrogen up to one-fifth by volume can be blended with CNG as fuel for buses.
4. H-CNG makes the fuel less expensive than CNG.
Which of the statements given above is/are correct?
H-CNG lowers carbon dioxide and hydrocarbon emissions, and hydrogen up to about a fifth by volume can be mixed into CNG for buses.
Read the full explanation →Hydrogen bomb is based on which Nuclear process?
A hydrogen bomb, also called a thermonuclear bomb, uses a fission explosion only as a trigger; the main energy comes from the fusion of the heavy hydrogen isotopes deuterium and tritium into helium at temperatures of millions of degrees, which is why the process is described as thermonuclear or thermal…
Read the full explanation →The first Union Territory of India to run 100 percent on solar energy is:
Diu, on the coast of Gujarat, was declared the first union territory in India to run entirely on solar power.
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