S&T 2023 Flashcards
(28 cards)
What is the carbon content percentage that defines carbon fibres?
90% or above
Carbon fibres are produced from organic fibres through thermal conversion.
What are the main advantages of carbon fibres?
- High tensile strength
- High stiffness
- Low density
- High chemical resistance
These characteristics make carbon fibres ideal for various applications, including automotive and aerospace industries.
True or False: Carbon fibres can be recycled.
True
Carbon fibres are difficult to recycle, but recycling can save energy and allow for their use in various applications.
What is the function of an accelerometer?
Measures vibration and acceleration of motion
Accelerometers convert mechanical force into electrical current using the piezoelectric effect.
How does an accelerometer contribute to car crash detection?
Measures g-force accelerations and sends signals to airbag control unit
This triggers the inflation device to protect passengers during a crash.
What is a Cepheid?
A star that brightens and dims periodically
Cepheids are used as cosmic yardsticks due to their regular brightness periods.
What is a nebula?
A giant cloud of dust and gas in space
Nebulae can be regions where new stars are forming or remnants of dying stars.
What are pulsars?
Neutron stars that emit pulses of radiation
They are formed when massive stars run out of fuel and collapse.
What is the James Webb Space Telescope primarily designed to do?
Examine every phase of cosmic history
It aims to observe the formation of galaxies, stars, and planets and analyze the atmospheres of extrasolar planets.
Which country has its own Satellite Navigation System?
Japan
Japan’s Quasi-Zenith Satellite System (QZSS) complements GPS for improved coverage.
Fill in the blank: A ballistic missile follows a _______ trajectory to deliver warheads.
parabolic
Ballistic missiles are propelled only during the initial phase of flight.
What distinguishes cruise missiles from ballistic missiles?
Cruise missiles are jet-propelled at subsonic speeds throughout their flight
Ballistic missiles are rocket-powered only during the initial phase.
What is the ‘Wolbachia method’ used for?
Controlling the spread of viral diseases transmitted by mosquitoes
Wolbachia is a bacterium that reduces the ability of mosquitoes to transmit diseases.
What is the range of Agni-V?
Over 5,000 km
Agni-V is an Inter-Continental Ballistic Missile (ICBM) developed by India.
What type of missile is BrahMos?
2 stage Long-range nuclear capable supersonic cruise missile - Mach 3 - Stealth capability - Fire & forget principle -
BrahMos is the fastest cruise missile in the world, capable of being launched from all 3 platforms.
True or False: Agni-V is a cruise missile.
False
Agni-V is a ballistic missile, whereas BrahMos is a cruise missile.
What is the Wolbachia method used for?
Controlling the spread of viral diseases transmitted by mosquitoes
The Wolbachia method specifically targets diseases like dengue, Zika, and chikungunya by introducing the bacterium Wolbachia into mosquito populations.
What is Wolbachia?
A type of bacterium that can reduce mosquitoes’ ability to transmit viral diseases
Wolbachia-infected mosquitoes mate with non-infected ones, resulting in eggs that do not hatch.
What are the primary vectors for dengue disease?
Aedes aegypti and Ae. albopictus mosquitoes
These mosquitoes are responsible for transmitting dengue, chikungunya, yellow fever, and Zika infection.
How many dengue virus serotypes exist?
Four: DEN-1, DEN-2, DEN-3, and DEN-4
Serotypes refer to separate groups within a species of microorganisms with similar characteristics.
What does aerial metagenomics refer to?
Collecting and analyzing DNA samples from air or aerosol particles in a habitat
This method captures the genetic material present in microorganisms from the air.
What are microsatellites?
Regions of repetitive DNA where a specific sequence of 2-6 base pairs is repeated
Microsatellites are also known as short tandem repeats (STRs) and are used for genetic markers.
What is green hydrogen?
Hydrogen generated by renewable energy or low-carbon power
Green hydrogen has lower carbon emissions compared to grey hydrogen and can be produced through water electrolysis.
Which applications can green hydrogen be used for?
Direct fuel for internal combustion, blended with natural gas, hydrogen fuel cells for vehicles
Green hydrogen can also decarbonize hard-to-electrify sectors and produce green ammonia.
