1. Which radioactive pollutant has recently drawn the attention of the public, due to its occurrence in the building material?
Radon is a radioactive gas that occurs naturally from the decay of uranium, and it has raised public concern due to its presence in building materials and as an indoor air pollutant. It is a leading cause of lung cancer after smoking.
2. Permanent hardness of water can be removed by adding
Washing soda (sodium carbonate, Na2CO3) can be used to remove permanent hardness of water by precipitating calcium and magnesium ions as their respective carbonates. This process softens the water.
3. The mixed oxide fuel is used for which of the following?
Mixed oxide (MOX) fuel is a type of nuclear fuel consisting of a blend of uranium and plutonium oxides. It is primarily used in nuclear reactors as a way to recycle plutonium from spent nuclear fuel and reduce the amount of radioactive waste.
4. Bar is the unit of
Bar is a unit of pressure, commonly used to measure atmospheric pressure. One bar is approximately equal to the atmospheric pressure at sea level, which is 100,000 pascals.
5. What are soaps?
Soaps are typically formed by the reaction of sodium or potassium hydroxide with fatty acids. This process, known as saponification, results in the formation of soap molecules that have hydrophilic (water-attracting) and hydrophobic (water-repelling) properties.
6. In radar system, the transmitting antenna is of
In radar systems, the transmitting antenna typically rotates in the azimuth (horizontal plane) to scan a wide area. This allows the radar to detect objects in various directions by emitting radio waves and receiving their reflections.
7. The inert gas which is substituted for nitrogen in the air, used by deep sea
drivers for breathing, is
Helium is used as a substitute for nitrogen in breathing mixtures for deep-sea divers. This is because helium is less soluble in the bloodstream and reduces the risk of nitrogen narcosis, a condition that can affect divers at great depths.
8. Amalgams are
Amalgams are alloys that contain mercury. They are commonly used in dental fillings, where mercury is combined with metals like silver, tin, or copper to form a durable material.
9. Actinides are the elements with atomic numbers from
The actinides are the series of elements with atomic numbers from 89 (actinium) to 103 (lawrencium). These elements are typically radioactive and include uranium, thorium, and plutonium, among others.
10. Human body needs a constant supply of proteins to survive. The first part
of the digestive system to begin digesting proteins is
The stomach is the first part of the digestive system where protein digestion begins. It secretes gastric juices containing pepsin, an enzyme that breaks down proteins into smaller peptides, and hydrochloric acid, which creates an acidic environment to aid enzyme activity.
11. The average salinity of sea water is
The average salinity of seawater is about 35 parts per thousand (‰), which means 35 grams of dissolved salts per kilogram of seawater. This is equivalent to 3.5%.
12. Which one of the following is used for dating archaeological specimens in
words, bones and shells?
Carbon-14 dating, also known as radiocarbon dating, is commonly used to determine the age of archaeological specimens such as wood, bones, and shells. This method is based on the radioactive decay of the carbon-14 isotope.
13. Chemical formula for water glass is
Water glass, also known as sodium silicate, has the chemical formula Na₂SiO₃. It is commonly used in adhesives, coatings, and as a sealant.
14. The pitch of the voice of woman is in general
The pitch of a woman’s voice is generally higher than that of men due to shorter and thinner vocal cords, which vibrate at a higher frequency.
15. Nuclear fission is caused by the impact of
Nuclear fission occurs when a heavy nucleus splits into smaller nuclei upon being hit by a neutron, releasing a large amount of energy.
16. The scientists released world’s smallest stop motion film called ‘A Boy
and His Atom’ by
IBM scientists created the world’s smallest stop-motion film, A Boy and His Atom, by moving individual atoms to form each frame. It holds a Guinness World Record.
17. Which country launched first ever deep UV laser device?
China launched the first-ever deep UV laser device, a significant milestone in advanced laser technology and applications in fields like healthcare and environmental monitoring.
18. Which of the following waves are used for telecommunication?
Microwaves are widely used for telecommunication purposes, including satellite communication, mobile networks, and wireless technologies, due to their ability to transmit signals over long distances with minimal interference.
19. NASA satellite data found freshwater losses during the past decade in
NASA satellite data revealed significant freshwater losses in the Middle East over the past decade, primarily due to over-extraction of groundwater for agriculture and other human activities, compounded by climate change.
20. The first complete bionic man of the world unveiled at London’s Science
Museum called
Rex is the name of the first complete bionic man, unveiled at London's Science Museum. The bionic man was designed using prosthetic technology, robotics, and artificial organs.
21. On January 5, 2014 India launched which satellite?
India launched the GSAT-14 satellite on January 5, 2014, using the GSLV (Geosynchronous Satellite Launch Vehicle) from the Satish Dhawan Space Centre. This satellite was meant to enhance communication and broadcasting services.
22. In January, 2014, a gray whale species has been found in
In January 2014, a new gray whale species was discovered in the waters off Baja California, Mexico. This species was found to be distinct from the other known populations of gray whales.
23. Inventor and founder of www is
Tim Berners-Lee is the inventor and founder of the World Wide Web (WWW). He developed the first website and the HTTP protocol in 1989 while working at CERN.
24. The oldest super predator living on earth discovered was the
The oldest super predator living on Earth discovered was the marine crocodile, specifically the "Boar Croc" (Kaprosuchus saharicus), which lived around 100 million years ago during the Cretaceous period.
25. Study of life in outer space is
Exobiology, also known as astrobiology, is the study of life in outer space, including the potential for life beyond Earth and the conditions under which life might arise or exist on other planets.
26. First 100 percent ultrasound toothbrush of the world developed by the
scientists of
The first 100% ultrasound toothbrush was developed by scientists in the United States. Robert T. Bock patented the toothbrush in 1992, and the FDA approved it for home use that same year. The toothbrush was originally called Ultima, but was later renamed Ultrasonex
27. India was affected by the cyber spying campaign called
India was impacted by the cyber espionage campaign called "Red October." This campaign, which lasted for several years, targeted government agencies, diplomatic institutions, and energy companies worldwide, including India.
28. ISRO’s 100th space mission completed by the launch of
The Indian Space Research Organization's (ISRO) 100th space mission was indeed PSLVC-21, launched on September 9, 2012, from the Satish Dhawan Space Centre in Sriharikota, Andhra Pradesh. It successfully carried the RISAT-1 (Radar Imaging Satellite-1) into orbit.
29. NASA recently marks 10th anniversary of space shuttle disaster of
NASA recently marked the 10th anniversary of the space shuttle disaster of Columbia. The disaster occurred on February 1, 2003, when the space shuttle disintegrated during re-entry into the Earth's atmosphere, tragically killing all seven astronauts aboard.
30. Which one of the following subjects is not related to ‘Robot’?
Hydraulics deals with fluid dynamics, not directly related to robots. Robotics is more linked to mechanics, cybernetics, and kinematics, which focus on motion, control, and systems.