Science and Technology MCQ Set 15
Showing question 71 to 75 of total 301 MCQs
MCQ Set: 15
Solve the question on your notebook and check it by clicking (Answer and Explanation) below question.
Question No: 71
Twitter allows how many characters in a single tweet?
- 140
- 150
- 250
- 280
Answer and Explanation
Answer: D
Explanation
Twitter is testing allowing tweets to be expanded to 280 characters - double the existing limit - in the latest effort to boost flagging growth at the social network.
San Francisco-based Twitter said on 26th Sept 2017 that the new limit, a major shift for the messaging platform known for its 140-character tweets, aims to address “a major cause of frustration” for many users.
Twitter chief executive Jack Dorsey fired off what may be one of the first expanded tweets.
“This is a small change, but a big move for us,” he wrote, calling the previous limit was an “arbitrary choice”.
Twitter planned to leave the old limit in place for tweets in Japanese, Chinese and Korean because internal data showed written characters in those languages packed plenty into the allotted space.
Twitter, which became a public company in 2013, has never reported a profit, even though it has built a loyal base of celebrities, journalists and political figures, including prolific tweeter US President Donald Trump.
In its most recent quarter, Twitter reported its base of monthly active users was unchanged at 328 million compared to the first three months of the year and up just five percent from a year earlier.
Its growth has failed to keep pace with social network leader Facebook, which has some two billion users, and Facebook-owned Instagram, with 800 million.
Twitter has been seeking to draw in users by offering more video, including live streaming of sporting events, aiming to broaden its appeal.
Reaction on Twitter was mixed, with some lobbying for the original cap and the pressure it applied to succinctly express thoughts.
Many others on Twitter welcomed the news and said raising the character cap was long overdue.
Some people already resort to long strings of rapid-fire tweets, known as “Twitter storms,” to string together lengthy comment.
The messaging platform reported a net loss of $116 million in the second quarter, slightly wider than its $107 million loss a year ago.
It remained an open question whether the new tweet limit would ignite the growth an engagement Twitter needs to compete in the fast-moving social media segment.
The move by Twitter could also be rendered moot by lifestyle changes brought about by trends in voice-commanded digital assistants and looking at the world through mixed-reality glasses, according to Gartner analysts.
Question No: 72
Which of the following is the first private spacecraft to be launched?
- SpaceShipOne
- Falcon X
- Cassini
- Mars Rover
Answer and Explanation
Answer: A
Explanation
The dream of building world's largest aircraft is a step closer to reality with the private spaceflight company Stratolaunch, which is spearheading the project, having successfully hit a milestone last week by completing the first phase of engine testing.
Stratolaunch was founded by Paul G. Allen, the man who funded first private spacecraft SpaceShipOne to carry a civilian into suborbital space and safely home again.
It aims at providing convenient, reliable, and routine access to low Earth orbit (LEO) that will help researchers collect data in science, research, and technology from space.
The team has completed fuel testing that includes testing all six fuel tanks to ensure proper operations and each of the six fuel tanks were filled independently to ensure proper operations of fuel mechanisms and to validate the tanks were properly sealed.
The company said that they have also begun testing the flight control system and have so far exercised the full limits of motion and rate of deflection of control surfaces on the wing and stabilisers.
The engine testing was conducted with a build-up approach consisting of three phases - dry motor, wet motor and then each engine was started one at a time and allowed to idle.
Each of the engines operated as expected.
The company would “continue to test the aircraft's engines at higher power levels and varying configurations, culminating to the start of taxi tests.”
Stratolaunch: World's Largest Aircraft
It is the world's largest aircraft by wingspan and is the largest all-composite plane ever built, according to Stratolaunch website.
It uses "Boeing 747 engines for a payload capacity of over 500,000 lbs
It has an operational range of approximately 2,000 nautical miles.
Wing span: 385 feet
Length: 238 feet
Tail height: 50 feet
Propulsion: 6X Pratt & Whitney PW4056 Engines
Max takeoff weight: 1,3000,000 LBS
Stratolaunch is expected to be fully operational by the end of this decade.
It is currently under construction at the Mojave Air & Space Port in Mojave, California.
Question No: 73
Researchers have found large chunks of which material near the North Pole, raising fears the material will be released into the Arctic Ocean?
- Plastic
- Formaldehyde
- Cadmium
- Polystyrene
- Only a and d
Answer and Explanation
Answer: D
Explanation
According to reports, scientists have discovered sizeable chunks of plastic near the North Pole, raising fears that melting ice will allow more of the material to be released into the Arctic Ocean - with detrimental effects on wildlife.
A team of scientists found polystyrene chunks 1,609 kilometres from the North Pole in the area that was previously inaccessible because of sea ice.
They found two large pieces on the edge of ice flows between 77 degree and 80 degree north, in the middle of the international waters of the central Arctic Ocean.
It is one of the most northerly sightings of such debris in the world's oceans, which are increasingly polluted by plastics and confirm just how far plastic pollution has spread.
This comes at a time when climate change-induced melting of Arctic ice has been a pressing matter for scientists across the world.
The finding has prompted fears that as the ice melts, because of climate change, plastic that has long been trapped in it is flowing into the Arctic.
Finding pieces of rubbish like this is a worrying sign that melting ice may be allowing high levels of pollution to drift into these area.
This is potentially very dangerous for the Arctic's wildlife.
More than five trillion pieces of plastic are estimated floating on the surface of the world's oceans.
It has been claimed that there is now enough plastic to form a permanent layer in the fossil record.
A significant concern is that large plastic pieces can break down into “micro plastics” that are tiny particles that are accidentally consumed by filter-feeding animals.
The particles remain in animals' bodies and are passed up the food chain, threatening wildlife at all levels from zooplankton to apex predators such as polar bears.
Many rivers that are often a source of plastic pollution lead into the Arctic Ocean, but plastic pollution has been literally trapped into the ice.
Now the ice is melting scientists believe micro plastics are being released into the Arctic.
Some projections indicate that the entire Arctic Ocean will be ice-free in summer by 2050, allowing human exploitation such as commercial fishing, shipping and industry of the newly opened waters.
Plastic Waste: Know More
Plastic waste is a menace that is the result of industrialization and to an extent, human activities, without realizing that it ends up affecting our health as well.
Plastic is considered inexpensive and durable, which is why it is most commonly used for packaging.
However, due to its slow degradation process, plastics can severely affect living organisms, especially marine life, through entanglement, direct ingestion of plastic waste, or through exposure to chemicals within plastics that cause interruptions in biological functions
Question No: 74
Which of the following have volcanic features like Earth, such as lava tubes?
- Mars
- Moon
- Venus
- All of the above
Answer and Explanation
Answer: D
Explanation
Like on Earth, Moon and Mars also have volcanic features - such as lava tubes.
Lava tubes are basically lava caves formed in one of two ways: either through the crusting over of lava channels, or more rarely, from pahoehoe flows where the lava is moving under the surface. After the lava leaves, it can leave behind a tunnel.
Sometimes, the lava might re-emerge and might be injected into its old tunnels (due to the low resistance); once there, it expands and leaves behind even larger tunnels, sometimes reaching impressive sizes.
Sometimes, complex tunnel systems are formed, connected to each other and to the surface.
By far the largest known lava tubes in the Solar System are on Venus. However, such tubes have also been discovered on the Moon, and especially on Mars.
Considering the innumerable lava flows and lava channels on the flanks of Olympus Mons, it makes a lot of sense to expect truly gargantuan lava tube systems on the Red Planet.
Scientists now believe that these tunnels can be used to shield future explorers from the massive amounts of radiation they would be exposed to on the surface.
Researchers can detect these tunnels remotely, through gravitational remote sensing. Things stand like this: we talk about the gravitational pull of a celestial body (let’s say, the Earth), but the gravitational field isn’t uniform.
The same goes for the Moon, Mars, and everything else — nothing is really uniform.
By studying localized gravitational anomalies, underground cavities - such as lava tunnels - can be discovered. But researchers are also working on more advanced methods.
A concept for a radar system specifically designed to detect lava tubes on the Moon from orbit was presented.
The idea is to send an electromagnetic pulse towards the planet and then detect a specific signature associated with these tunnels.
Although it’s still early stages, there are promising results which may be used in the near future.
The studies we have developed show that a multi- frequency sounding system is the best option for detecting lava tubes of very different dimensions.
The electromagnetic simulations show that lava tubes have unique electromagnetic signatures, which can be detected from orbit irrespective of their orientation to the radar movement direction.
Therefore, a mission carrying this instrument would enable a crucial step towards finding safe habitats on the Moon for human colonisation.
Geologists have also learned that the distribution of such systems can be generous enough to facilitate the establishment of large stations, or perhaps even entire cities.
On Earth, they can be up to thirty metres across. In the lower gravity environment of Mars, we see evidence for lava tubes that are 250 metres in width.
On the Moon, these tunnels could be a kilometre or more across and many hundreds of kilometres in length,.
Lava tubes are environments shielded from cosmic radiation and protected from micrometeorites flux, potentially providing safe habitats for future human missions.
They are also, potentially, large enough for quite significant human settlements - you could fit most of the historic city centre of Riga into a lunar lava tube, for example
Question No: 75
India is set to launch which new technology for expanding the potential of the networked society?
- 5G
- IoT
- Big Data
- AI
Answer and Explanation
Answer: A
Explanation
India is at the cusp of a next generation of wireless technology 5G. 5G has been conceived as a foundation for expanding the potential of the Networked Society.
A digital transformation brought about through the power of connectivity is taking place in almost every industry.
The landscape is expanding to include massive scale of “smart things” to be interconnected. Therefore, the manner in which future networks will cope with massively varied demands and a business landscape will be significantly different from today.
The economic benefits from the 5G technology are also quite immense.
As per the OECD (Organization for Economic Cooperation and Development) Committee on Digital Economic Policy, it has been stated that 5G technologies rollout will help in,
a. Increasing GDP
b. Creating Employment
c. Digitizing the economy.
For India, 5G provides an opportunity for industry to reach out to global markets, and consumers to gain with the economies of scale.
Worldwide countries have launched similar Forums and thus, India has joined the race in 5G technologies. We are open for collaboration with them.
Government has constituted High Level 5G India 2020 Forum with three Secretaries of key Ministries/Departments Telecom, Meity and DST, and also comprising of renowned experts and Professors from IIT Madras, IIT Mumbai, IIT Delhi, IIT Hyderabad, IISc Bengaluru, IT industry and stakeholders from industry associations.
The Term of Reference of the High Level Forum for 5G India 2020 shall be:-
a. Vision Mission and Goals for the 5G India 2020, and
b Evaluate, approve roadmaps & action plans for 5G India 2020.
The primary goals of the forum are to achieve:
early deployment of 5G in India
a globally competitive product development and manufacturing ecosystem targeting 50% of India market and 10% of global market over next 5 to 7 years.
The forum will complement the eco-system by focused actions in the following areas:
Research Ecosystem - for IPR development, standards development and proof of concepts through research projects, PPP projects, testbeds and pilot roll-outs.
Regulatory Framework - including spectrum assignments and a start-up friendly regulatory environment to enable leap-frog and embracing of innovative technologies.
Inclusive Business environment - with special focus on investment incentives favourable to start-ups and innovators and enablement of Venture capitalists.
Forum will constitute a number of Steering Committees in different domains.
A vibrant eco-system of research built around 5G that encompasses Industry, Government and Academia will further strengthen the MAKE (& DESIGN) in INDIA initiatives to enable:
Design and manufacture of 5G technologies, products and solutions in India;
5G start-ups that enable this design and manufacturing capabilities;
Generation of IPR backing the above designs;
India based companies should have some essential IPR in the 5G standard;
Manufacture of 5G chipsets, this may require massive investments;
Appropriate testbeds and technology platforms to enable and help Indian technical ecosystem to have an edge in 5G;
Accelerated deployment of next generation ubiquitous ultra-high broadband infrastructure with 100% coverage of 10 Gbps across urban India and 1 Gbps across Rural India.