Science and Technology MCQ Set 47
Showing question 231 to 235 of total 301 MCQs
MCQ Set: 47
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Question No: 231
Which is the last living dinosaur prior to the asteroid strike 66 million years back?
- Chenanisaurus barbaricus
- Dhenanisaurus barbaricus
- Thenanisaurus barbaricus
- Shenanisaurus barbaricus
Answer and Explanation
Answer: A
Explanation
The fossil of one of the last living African dinosaur was discovered in a phosphate mine in northern Morocco.
The species, Chenanisaurus barbaricus, is reportedly one of the last ones to have survived on Earth before an asteroid strike wiped them out 66 million years ago
The project was carried out as a part of an international scientific collaboration that aims to conserve Morocco’s rich fossil heritage by helping create and study the country’s palaeontology collections.
The fossil study is being led by Milner Centre for Evolution at the University of Bath.
Its analysis suggests that a distinct dinosaur fauna evolved in Africa following the breakup of the Gondwana supercontinent in the middle of the Cretaceous period.
The new species is understood to be the smaller African contemporary of the North American T-Rex.
Almost nothing is known about the dinosaurs that lived in Africa at the end of the Cretaceous period 66 million years ago, just before their extinction.
Most of the fossils have been discovered from marine rocks.
The study revealed that the fragment belonged to an abelisaur, two-legged predators like T. rex and other tyrannosaurs with a shorter snout and tinier arms.
The species were known to be the top predators at the end of the Cretaceous period in Africa, South America, India, and Europe.
Unlike the abelisaurs, who had very short arms, the newly discovered dinosaur- Chenanisaurus barbaricus- stood on two legs and had stumpy arms.
The study of the fossil’s worn-out teeth reveals that it was a predator and unlike the partially feathered T. rex, Chenanisaurus had only scales and its brain was much smaller and its face, shorter and deeper.
Dinosaurs: Know More
Dinosaurs are known to have lived between 230 and 65 million years ago, a period that is known as the Mesozoic Era.
The period is many million years before the first modern humans, Homo sapiens, appeared.
Scientists divide the Mesozoic Era into three periods: the Triassic, Jurassic and Cretaceous.
The Cretaceous Period was the last and longest period of the Mesozoic Era.
It began 145 million years ago and ended 66 million years ago, lasting for approximately 79 million years. It followed the Jurassic period and ended with the extinction of the dinosaurs.
The period may have seen more dinosaurs than ever before.
Some of the dinosaur species that evolved during this time include Triceratops, Centrosaurus, armoured Ankylosaurus and the large carnivore Tyrannosaurus.
Question No: 232
Which IIT developed white light emission using natural extracts red pomegranate and turmeric?
- IIT-K
- IIT-D
- IIT-B
- None of the above
Answer and Explanation
Answer: D
Explanation
IIT Madras has won the BIRAC Gandhian Young Technological Innovation (GYTI) Award 2017 for its work on producing white light emission using natural extracts.
Scientists from the Department of Chemistry, IIT Madras used a mixture of two natural extracts - red pomegranate and turmeric - to produce white light emission.
The researchers used a simple and environment-friendly procedure to extract dyes from pomegranate and turmeric.
While polyphenols and anthocyanins present in red pomegranate emit at blue and orange-red regions of the wavelength respectively, curcumin from turmeric emit at the green region of the wavelength.
White light emission is produced when red, blue and green mix together.
This is probably the first time white light emission has been generated using low-cost, edible natural dyes.
By changing the concentration of the two extracts the researchers were able to get different colour temperature (tunability).
When the two extracts and irradiate it with UV radiation at 380 nm, scientists observed energy transfer (FRET mechanism) taking place from polyphenols to curcumin to anthocyanins, which helps to get perfect white light emission.
For FRET mechanism to take place there must be spectral overlap between the donor and acceptor.
In this case, there is a perfect overlap of emission of polyphenols with absorption by curcumin so the energy from polyphenols is transferred to curcumin.
Since there is also a perfect overlap of emission of curcumin with absorption by anthocyanin, the energy of curcumin is transferred to anthocyanin.
As a result of this energy transfer from one dye to the other, when the extract is irradiated with UV light at 380 nm (blue region of the wavelength), the polyphenols emit in the blue region of the wavelength and transfers its energy to curcumin.
The excited curcumin emits in the green region of the wavelength and transfers its energy to anthocyanin, which emits light in the red region of the wavelength.
Scientists carbon nanoparticles using pomegranate and to their surprise it was producing fairly green emission.
So instead of using turmeric to get green wavelength, the researchers used carbon nanoparticles made from pomegranate extract. “
Though this natural mixture of dyes can be used in a wide variety of applications such as tunable laser, LEDs, white light display, much work needs to be done in terms of photostability and chemical stability before it becomes ready for translation.
Biosystems have an inherent tendency to breakdown and so this has to be addressed.
Question No: 233
What is true about the world’s fastest film camera?
- Capable of taking 5 trillion images per second
- Capturing a single image every 0.2 trillionths of a second
- Capable of visualising the movement of light
- Only a and b
- All of the above
Answer and Explanation
Answer: E
Explanation
World’s fastest film camera can ‘capture’ light.
As per Einstein’s theory, nothing can travel faster than the speed of light in a vacuum that makes it difficult to capture.
Now researchers at Lund University in Sweden have built the world’s fastest film camera that is capable of taking five trillion images per second.
This means an image every 0.2 trillionths of a second.
In other words, the camera is fast enough to visualize the movement of light or capture molecular processes.
The camera could be used to observe extremely rapid natural processes and reactions in chemistry, physics, biology and biomedicine that until now have not been captured on film.
The researchers exposed an object to be filmed to brief flashes of laser light, which were reflected by the object.
The new technology called Frequency Recognition Algorithm for Multiple Exposures (FRAME) is based on an innovative algorithm.
It instead captures several coded images in one picture and later sorts them into a video sequence.
This method took four separate images per frame instead of taking images one by one in a sequence, like other high-speed cameras.
Question No: 234
Which scientific organisation has developed India's first indigenous solar hybrid electric car?
- DRDO
- CSIR
- TIFR
- ISRO
Answer and Explanation
Answer: D
Explanation
ISRO demonstrated its solar hybrid electric car and there's a strong reason behind working on it.
Vehicles using fossil fuels persistently bring serious problems to environment and life.
In this perspective, Solar and Electrical energy based hybrid vehicles provide the most effective and viable long-term solution by using renewable energy sources for mobility.
Vikram Sarabhai Space Centre (VSSC), ISRO, Thiruvananthapuram, demonstrated the running of a solar hybrid electric car using in-house expertise and resources within ISRO.
Considerations involved the right solar panel to suit the roof top of car, a super-capacitor to meet the high peak current of beyond 100 A level, an integral gear box to augment the performance of the Brushless DC (BLDC) motor.
It also involved control electronics for the battery and solar panel interface and drive electronics for running the motor in a smooth way.
The biggest one of course was the conversion of the internal combustion engine (ICE) based vehicle, which was a Maruti Suzuki Omni, to fit in with the electric motor.
The Brushless motor had to be modified to improve torque
To drive the car, energy was supplied to the vehicle by energy density Lithium ion batteries connected across high power density super-capacitors.
The battery delivered the sustained energy requirement while the super-capacitor supported the peak power demand during high torque conditions.
This arrangement of power sharing helped in enhancing the life of power-restricted batteries.
Energy was supplied to the vehicle by energy density Lithium ion batteries.
A solar panel fitted on rooftop of the car charges the battery by absorbing the sunlight.
How it Works
This electrical energy needed to be converted to mechanical energy to drive the wheels.
This was achieved by integrating an efficient power conversion module between energy system and electric motor.
The usage of a Brushless type motor helped in improving the torque and reducing energy input while also helping in weight savings.
Concerted efforts were made to ensure that the associated safety aspects are not compromised while combining various active subsystems of different behaviour for a focused objective.
Question No: 235
Which country/countries is/are set to create a national online encyclopaedia?
- Russia
- China
- India
- Both a and b
Answer and Explanation
Answer: D
Explanation
China has hired more than 20,000 people to build the country's online version of national encyclopaedia to compete with Wikipedia.
The Chinese Wikipedia will be launched in 2018 and will feature 300,000 entries at about 1,000 words each.
The Wikipedia of China will be created by select scholars from state-run universities unlike the original Wikipedia that is openly editable by volunteers.
Currently, Wikipedia is available in China but some of its contents are blocked.
The Encyclopaedia of China is not a book but a Great Wall of culture, according to the project's editor in chief.
The Encyclopaedia of China already exists in paper form that was first published in 1993. Its second edition was released in 2012.
Last week, Turkish authorities banned access to Wikipedia in the country without giving any particular reasons.
Aiming to provide better information about the country than what was already available on the Wikipedia, Russia in 2014 announced plans for an alternative version of the online encyclopaedia.