Science & Technology GK Questions with Answers – Page 15

The Japanese engineer Norio Taniguchi used the word nanotechnology in 1974 to describe machining to tolerances of a nanometre, and that is the coinage examiners expect.

The prefix nano stands for ten raised to the power minus nine, so one nanometre is one billionth of a metre, which is also ten angstrom, and nanotechnology is defined as work in the band of one to one hundred nanometres.

The International Solar Alliance was launched jointly by India and France at the Paris climate conference on 30 November 2015 to bring together countries lying largely between the tropics, and its headquarters is at Gwal Pahari in Gurugram, Haryana.

Free hydrogen does not occur in any usable quantity on earth, so it has to be made from water or from a hydrocarbon by spending energy, and it then stores and delivers that energy elsewhere.

A fuel cell converts the chemical energy of hydrogen directly into electrical energy without combustion, so it is not bound by the efficiency limit of a heat engine.

SIGHT is the largest component of the mission, with an outlay of seventeen thousand four hundred ninety crore rupees, and it has two parts: incentives for manufacturing electrolysers in India and incentives for producing green hydrogen, both awarded through competitive bidding.

The MNRE is the nodal ministry for the mission, frames the guidelines for each of its components and notified the Green Hydrogen Standard for India in August 2023.

The mission aims to build a green hydrogen production capacity of at least five million metric tonnes a year by 2030, with the potential to rise further if an export market develops, and this is the single figure most often asked from the mission.

The Union Cabinet approved the National Green Hydrogen Mission on 4 January 2023 with this outlay, to be spent up to the financial year 2029-30 across incentives, hubs, pilot projects, research and skilling.

The Ministry of New and Renewable Energy notified the Green Hydrogen Standard for India in August 2023, fixing the limit at two kilograms of carbon dioxide equivalent for each kilogram of hydrogen, averaged over twelve months, and covering the whole chain from water treatment through electrolysis, purification, drying and compression…

Blue hydrogen is made by the same fossil route as grey hydrogen, usually steam reforming of natural gas, but the carbon dioxide produced is captured and stored underground instead of being released, so its emissions are much lower though not zero.

Hydrogen is called green only when the electricity that splits the water comes from a renewable source such as solar or wind, so that no carbon dioxide is released in making it.

Diu, on the coast of Gujarat, was declared the first union territory in India to run entirely on solar power.

The three PARAM Rudra systems dedicated in 2024 under the National Supercomputing Mission went to the Giant Metrewave Radio Telescope near Pune for radio astronomy, the Inter-University Accelerator Centre at New Delhi for research in physics and materials, and the S. N. Bose National Centre for Basic Sciences at Kolkata…

The ladder of units rises by a factor of a thousand at each step: a megaflop is a million operations in a second, a gigaflop is a billion, a teraflop is a thousand billion, which is one trillion, and a petaflop is a thousand trillion.

The Top500 list has been published twice a year since 1993 and ranks the five hundred most powerful computer systems that have been measured, using the LINPACK benchmark, which times a machine while it solves a large system of linear equations.

SAGA-220 was built in 2011 at the Vikram Sarabhai Space Centre, Thiruvananthapuram, and its name stands for Supercomputer for Aerospace with GPU Architecture, the figure 220 marking a speed of about 220 teraflops.

Pratyush was commissioned in 2018 under the Ministry of Earth Sciences and is the larger of the two machines the ministry uses for weather and climate modelling.

A supercomputer is built for scientific calculation on decimal numbers, so the useful measure is how many such operations it finishes in a second, not how fast a single chip ticks.

The National Supercomputing Mission, launched in 2015, is run jointly by the Ministry of Electronics and Information Technology and the Department of Science and Technology, and the work on the ground is carried out by C-DAC Pune along with the Indian Institute of Science, Bengaluru.