All questions of Medical and Technological Developments for Grade 10 Exam

Jupiter's Moons Discovered by Galileo Galilei

Galileo Galilei, the Italian astronomer, is credited with the discovery of the four largest moons of Jupiter, namely Io, Europa, Ganymede, and Callisto. This significant discovery was made in 1610, during Galileo's observations of the night sky using a telescope.

The Discoveries:
- Io: Io is the innermost moon of Jupiter and the fourth-largest moon in the solar system. Galileo observed Io as a small point of light near Jupiter and noticed that it changed its position relative to the planet over time. This observation led him to conclude that Io was indeed a moon orbiting around Jupiter.

- Europa: Europa is the second moon of Jupiter in terms of distance from the planet. Galileo also observed Europa as a point of light near Jupiter, similar to Io, and noticed its changing position. He realized that Europa, like Io, was also a moon orbiting Jupiter.

- Ganymede: Ganymede is the largest moon in the solar system and the third of Jupiter's moons discovered by Galileo. It is larger than the planet Mercury and even some dwarf planets. Galileo observed Ganymede as a bright point of light near Jupiter and noticed its motion, confirming that it was another moon of Jupiter.

- Callisto: Callisto is the fourth and outermost of the four Galilean moons. Galileo observed Callisto as a faint point of light near Jupiter and observed its motion, similar to the other three moons. This discovery completed his observations of Jupiter's four largest moons.

The Significance of Galileo's Discoveries:
Galileo's discovery of the four largest moons of Jupiter was significant for several reasons:
1. It provided evidence against the geocentric model of the universe, which held that all celestial bodies revolved around the Earth. The existence of moons orbiting Jupiter supported the heliocentric model proposed by Nicolaus Copernicus, where the Earth and other planets revolve around the Sun.
2. Galileo's observations challenged the idea that celestial bodies were perfect and unchanging. The changing positions of the moons showed that they were independent bodies in motion, further undermining the prevailing Aristotelian view of the heavens.
3. The discovery of Jupiter's moons expanded our knowledge of the solar system and demonstrated that celestial bodies could have their own moons, similar to Earth's Moon.

In conclusion, Galileo Galilei is credited with the discovery of Jupiter's four largest moons - Io, Europa, Ganymede, and Callisto. His observations using a telescope in 1610 provided evidence for the heliocentric model and expanded our understanding of the solar system.

Explanation:
The correct answer is C: Copper nitrate. Copper nitrate is not used in photographic processing.
Here is a detailed explanation:
- Silver halide: Silver halide, such as silver bromide or silver chloride, is a key component in photographic film and paper. It is sensitive to light and forms the image when exposed to light during the photographic process.
- Ammonium thiosulphate: Ammonium thiosulphate, also known as hypo or fixer, is a chemical used in the fixing stage of photographic processing. It helps to remove any remaining light-sensitive silver halide from the film or paper, making the image permanent.
- Copper nitrate: Copper nitrate is not used in photographic processing. It is a chemical compound used in other applications such as catalysts, dyes, and electroplating.
- Both a and b: The option "both a and b" is incorrect because both silver halide and ammonium thiosulphate are used in photographic processing.
In summary, copper nitrate is not used in photographic processing, while silver halide and ammonium thiosulphate are essential chemicals in the process.

Introduction
The physicist in question is Louis Essen, an English scientist renowned for his contributions to the precise measurement of time and the speed of light.
Key Achievements
- Speed of Light Measurement:
Louis Essen was the first to measure the speed of light using a laboratory apparatus. This was a significant advancement in physics, as it moved the measurement from astronomical methods to controlled laboratory conditions.
- Development of Atomic Clocks:
Essen also played a pivotal role in the development of atomic clocks, which are crucial for accurate timekeeping and have applications in GPS technology and telecommunications.
Impact on Physics
- Precision in Measurements:
His work emphasized the importance of precision in scientific measurements. The methods he developed continue to influence timekeeping and measurements in physics today.
- Foundation for Future Research:
Louis Essen's findings laid the groundwork for future research and technological advancements related to time and light, impacting various fields of science and engineering.
Conclusion
In summary, Louis Essen's innovative approaches and methods in measuring the speed of light and time have made him a key figure in physics, distinguishing him from other scientists like Isaac Newton and B. Halt. His legacy continues to shape our understanding of fundamental scientific principles.

Introduction
The Hubble Space Telescope, launched in 1990, has undergone several servicing missions to maintain its functionality and enhance its capabilities. These missions have been crucial for extending the telescope's operational life and ensuring it delivers high-quality astronomical data.
Servicing Missions Overview
The Hubble Space Telescope has had a total of five servicing missions. Here’s a brief overview of each:

• Servicing Mission 1 (SM1): Launched in 1993, this mission aimed to correct the telescope's initial optical flaw with the installation of corrective optics.
• Servicing Mission 2 (SM2): Conducted in 1997, this mission upgraded the telescope’s instruments and added new capabilities, including the Wide Field and Planetary Camera 2.
• Servicing Mission 3A (SM3A): In 1999, this mission replaced gyroscopes and batteries, which were essential for Hubble's stability and power.
• Servicing Mission 3B (SM3B): Also in 2002, this mission further upgraded instruments and repaired the Space Telescope Imaging Spectrograph.
• Servicing Mission 4 (SM4): Launched in 2009, this final servicing mission installed new science instruments and enhanced capabilities, ensuring Hubble could continue its work for years to come.

Conclusion
Overall, the five servicing missions have been pivotal in maintaining the Hubble Space Telescope's status as one of the most important astronomical tools, allowing it to provide groundbreaking discoveries and stunning images of the universe.

Wasp Sting and its Remedy:
Wasp Sting:
- A wasp sting is the result of a wasp injecting venom into the skin.
- The venom contains several chemicals that cause pain, inflammation, and allergic reactions in some individuals.
Nature of Wasp Sting:
- Wasp stings are alkaline or basic in nature.
- The venom has a pH greater than 7, which means it is alkaline.
Remedy for a Wasp Sting:
- To neutralize the alkaline nature of the wasp sting venom, an acidic substance is required.
- The recommended remedy for a wasp sting is an acid, specifically vinegar or lemon juice.
- The acid helps to neutralize the venom, reducing pain and inflammation.
Answer:
- The correct answer is D: alkaline, acid.
- Wasp stings are alkaline in nature, and the remedy for a wasp sting is an acid to neutralize the venom's alkalinity.

The name of the space shuttle that launched the Hubble Space Telescope into orbit on April 24, 1990, is the Discovery.

Explanation:

The Hubble Space Telescope is a large telescope that was specifically designed to be placed in space to avoid the distortion caused by Earth's atmosphere. It was launched into orbit by the space shuttle Discovery.

The space shuttle Discovery was one of NASA's fleet of space shuttles that were used for various missions, including satellite deployments, crew rotations to the International Space Station (ISS), and telescope launches. It was the third operational orbiter in NASA's Space Shuttle program and played a crucial role in many significant missions.

The Discovery had a total of 39 successful missions during its operational life, making it the most flown orbiter in the shuttle fleet. It was first launched on August 30, 1984, and its final mission was on February 24, 2011.

The launch of the Hubble Space Telescope on April 24, 1990, marked an important milestone in space exploration. The telescope has provided humanity with breathtaking images of distant galaxies, stars, and nebulae, as well as valuable scientific data that has advanced our understanding of the universe.

In summary, the Hubble Space Telescope was launched into orbit by the space shuttle Discovery on April 24, 1990. The Discovery was one of NASA's space shuttles and played a significant role in space exploration missions.

Cellphone Calls and the Waves Used

Cellphone calls are made and received using radio waves. Radio waves are a type of electromagnetic wave that are used for transmitting and receiving information wirelessly. They have a longer wavelength and lower frequency compared to other types of waves such as sound waves or light waves.

How Radio Waves Work

Radio waves are generated by the cellphone and transmitted through the air. They carry the information in the form of changing electrical signals. These electrical signals are then converted into sound waves by the receiving cellphone, allowing the user to hear the person on the other end of the call.

Advantages of Using Radio Waves

There are several advantages of using radio waves for cellphone communication:

1. Long Range: Radio waves have the ability to travel long distances without significant loss of signal strength. This allows cellphone signals to be transmitted and received over large areas, enabling communication between people in different locations.

2. Penetration: Radio waves can penetrate through obstacles such as walls and buildings, allowing cellphone signals to reach indoor areas. This is important for ensuring that cellphone calls can be made and received even when the user is inside a building.

3. Multiple Users: Radio waves can be used by multiple users simultaneously without interference. This allows many people to make and receive cellphone calls in the same area without experiencing significant disruptions in signal quality.

Conclusion

In conclusion, cellphone calls are made and received using radio waves. These waves have the ability to transmit and receive information wirelessly, allowing users to communicate with each other over long distances. Radio waves offer advantages such as long range, penetration through obstacles, and the ability to accommodate multiple users simultaneously.

The world's 1st scanning helium microscope (SHeM) is developed by Australia.
Explanation:
The development of the world's first scanning helium microscope (SHeM) was done by Australia. Here is a detailed explanation of the answer:
- Scanning Helium Microscope (SHeM): The scanning helium microscope (SHeM) is a type of microscope that uses a beam of helium atoms to image and analyze samples at the atomic scale. It offers high-resolution imaging without damaging the sample.
- Development: The development of the SHeM was carried out by a team of researchers and scientists in Australia. They worked on designing and constructing the microscope, as well as developing the necessary technologies and techniques to make it functional.
- Significance: The development of the SHeM is a significant achievement in the field of microscopy. It opens up new possibilities for imaging and analyzing materials at the atomic scale, which can have applications in various fields such as materials science, nanotechnology, and biology.
- Australia's Expertise: Australia has a strong and vibrant scientific community, with expertise in various areas of research and development. The development of the SHeM showcases Australia's capabilities in cutting-edge scientific innovations.
In conclusion, the world's first scanning helium microscope (SHeM) was developed by Australia. This achievement highlights the country's expertise in the field of microscopy and its commitment to advancing scientific knowledge and technology.

Discovery of the Telescope by Galileo
Galileo Galilei, an Italian astronomer, physicist, and mathematician, is credited with the discovery of the telescope. Here is a detailed explanation of Galileo's role in the discovery:
1. Background:
- In the early 17th century, the concept of the telescope had already been proposed by astronomers like Hans Lippershey and Jacob Metius.
- However, Galileo was the first to build and use a telescope for astronomical observations.
2. Galileo's Telescope:
- Galileo developed his first telescope in 1609 by improving upon the design of existing telescopes.
- His telescope used a convex objective lens and a concave eyepiece lens, allowing for magnification and improved clarity.
3. Astronomical Observations:
- With his telescope, Galileo made several groundbreaking astronomical observations that revolutionized our understanding of the universe.
- He observed the moon's surface, discovering that it had mountains and craters, contradicting the prevailing belief in a perfect celestial sphere.
- Galileo also observed the phases of Venus, which supported the heliocentric model proposed by Nicolaus Copernicus.
- Moreover, he discovered the four largest moons of Jupiter, now known as the Galilean moons, which provided evidence for objects orbiting a celestial body other than the Earth.
4. Galileo's Contributions:
- Galileo's observations and discoveries using the telescope helped to support the Copernican heliocentric model of the solar system.
- His work challenged the geocentric model and the prevailing Aristotelian worldview, leading to significant scientific advancements.
In conclusion, Galileo Galilei is the scientist who discovered the telescope. His groundbreaking observations using the telescope played a crucial role in advancing our understanding of the cosmos and challenging the prevailing scientific beliefs of his time.

India launches GSAT-18 communication satellite from Guiana
India successfully launched its latest communication satellite GSAT-18 from Guiana on October 6, 2016. The satellite was launched aboard an Ariane 5 rocket from the Guiana Space Centre, Europe's spaceport in Kourou, French Guiana. Here are the key details:
Launch Location:
- The GSAT-18 satellite was launched from Guiana, a department of France located on the northeastern coast of South America.
- The Guiana Space Centre is operated by the French space agency, CNES, and is used to launch satellites for various countries.
Launch Vehicle:
- The satellite was launched using an Ariane 5 rocket, which is a heavy-lift launch vehicle operated by Arianespace.
- Ariane 5 is known for its reliability and efficiency, making it a preferred choice for satellite launches.
Objective of GSAT-18:
- GSAT-18 is a communication satellite designed to provide services in the Ku-band and extended C-band frequencies.
- Its main objective is to support telecommunications, television broadcasting, and VSAT services in India.
Specifications of GSAT-18:
- GSAT-18 has a mass of approximately 3,404 kilograms and is equipped with 48 communication transponders.
- It has a mission life of about 15 years and was built by the Indian Space Research Organisation (ISRO).
Significance of GSAT-18:
- GSAT-18 is an important addition to India's existing fleet of communication satellites.
- It will enhance the country's communication capabilities, especially in remote and rural areas, improving connectivity and enabling better access to telecommunication services.
In conclusion, India launched its latest communication satellite GSAT-18 from Guiana, using an Ariane 5 rocket. This satellite will play a crucial role in improving telecommunications, television broadcasting, and VSAT services in India, ultimately enhancing connectivity and accessibility across the country.

Benjamin Franklin's Musical Invention: Guitar
- Benjamin Franklin, well-known as a prolific inventor, was not only interested in science and politics but also had a passion for music.
- He invented a musical instrument, and that instrument is the guitar.
- Franklin created his version of the guitar, which was designed with a unique shape and structure.
- His guitar had a hollow body and a flat top with six strings that could be plucked or strummed.
- Franklin's guitar design was influenced by other stringed instruments such as the lute and the viola da gamba.
- Although Franklin's guitar design didn't gain significant popularity and didn't have a lasting impact on the development of the instrument, it showcased his inventive spirit and curiosity.
Other Notable Inventions and Achievements by Benjamin Franklin:
- Franklin's most famous invention is the lightning rod, which is used to protect buildings from lightning strikes.
- He also invented the Franklin stove, a more efficient heating device that provided better warmth while using less fuel.
- Franklin conducted extensive experiments on electricity and is known for his famous kite experiment, which proved that lightning is an electrical phenomenon.
- He discovered the Gulf Stream, a powerful ocean current that greatly influenced navigation and trade routes.
- Franklin played a crucial role in establishing the first public library in the United States, the Library Company of Philadelphia.
- In addition to these inventions, Franklin also made notable contributions in the fields of printing, writing, and diplomacy.
Overall, Benjamin Franklin's inventive mind and diverse interests led him to make significant contributions in various fields, including music with his invention of the guitar.

Answer:
The Nobel Prize in Chemistry, 2015 was awarded to the following scientists for their "mechanistic studies of DNA repair":
Tomas Lindahl
- Tomas Lindahl was awarded the Nobel Prize in Chemistry in 2015.
- He was recognized for his work on DNA repair mechanisms.
- His research focused on understanding how cells repair damaged DNA and maintain its integrity.
- Lindahl discovered several DNA repair enzymes and pathways, including the base excision repair pathway.
Paul L. Modrich
- Paul L. Modrich was another recipient of the Nobel Prize in Chemistry in 2015.
- His work also contributed to the understanding of DNA repair.
- Modrich studied the mismatch repair pathway, which corrects errors that occur during DNA replication.
- His research helped elucidate the molecular mechanisms of mismatch repair and its importance in maintaining genomic stability.
Aziz Sancar
- Aziz Sancar was the third scientist awarded the Nobel Prize in Chemistry in 2015.
- He made significant contributions to the field of DNA repair.
- Sancar focused on understanding the nucleotide excision repair pathway, which repairs DNA damage caused by ultraviolet radiation.
- His research provided insights into the mechanisms of DNA repair and its role in preventing mutations and cancer.
All of these
- In summary, the Nobel Prize in Chemistry in 2015 was awarded to Tomas Lindahl, Paul L. Modrich, and Aziz Sancar for their pioneering work on the mechanistic studies of DNA repair.
- Their research has advanced our understanding of how cells maintain the integrity of their genetic material and has important implications for human health and disease.

The name of the satellite launched by China's space lab Tiangong-2 is Banxing-2. Here is a detailed explanation:
Background:
China's space lab, Tiangong-2, was launched on September 15, 2016. It was an experimental space station used for various scientific research and technological demonstrations.
The Satellite:
The Banxing-2 satellite, also known as BX-2 or "Companion Satellite 2," was deployed from the Tiangong-2 space lab. It was a small satellite developed by China and had specific objectives during its mission.
Objectives of Banxing-2:
The Banxing-2 satellite had the following objectives:
1. Earth Observation: It was equipped with cameras to capture images of the Earth's surface. These images were used for scientific research, environmental monitoring, and disaster prevention purposes.
2. Technology Demonstration: Banxing-2 was used to test and demonstrate various technologies and systems related to space exploration. It aimed to gather data and validate the performance of these technologies in space.
3. Space Station Monitoring: The satellite was also tasked with monitoring and observing the Tiangong-2 space lab itself. It provided valuable data on the conditions and performance of the space station.
4. Educational Outreach: Banxing-2 carried a student-designed experiment to promote science education and encourage young students to take an interest in space exploration.
Conclusion:
The satellite launched by China's space lab Tiangong-2 was named Banxing-2. It had specific objectives related to Earth observation, technology demonstration, space station monitoring, and educational outreach.

The 2nd largest black hole in the Milky Way was found by Japan. Here is a detailed explanation of the discovery:
Background:
The Milky Way is a galaxy that contains billions of stars, and at the center of the galaxy lies a supermassive black hole called Sagittarius A*. Scientists have been studying this black hole and its surrounding environment for many years.
The Discovery:
In 2019, a team of Japanese astronomers made a significant discovery regarding a black hole in the Milky Way. Using the data from the ALMA (Atacama Large Millimeter/submillimeter Array) telescope in Chile, they found a black hole that is estimated to be the 2nd largest in our galaxy.
Key Points:
- The black hole found by Japan is the 2nd largest in the Milky Way.
- The discovery was made using data from the ALMA telescope in Chile.
- The ALMA telescope is an international collaboration, but the Japanese team played a crucial role in analyzing the data and making the discovery.
Conclusion:
In conclusion, the 2nd largest black hole in the Milky Way was found by Japan. This discovery was made possible through the use of the ALMA telescope and the dedicated efforts of the Japanese astronomers involved in the research.

Who invented Dynamite?
Answer: Alfred B. Nobel
Detailed
Dynamite was invented by Alfred B. Nobel. Here is a detailed explanation of his invention:
1. Alfred B. Nobel:
- Alfred B. Nobel was a Swedish chemist, engineer, and inventor.
- He was born on October 21, 1833, in Stockholm, Sweden.
- Nobel held 355 different patents and made significant contributions to various fields, including chemistry, engineering, and physics.
2. Invention of Dynamite:
- Nobel invented dynamite in the late 1860s.
- Dynamite is an explosive material that is widely used in construction, mining, and warfare.
- It is a stable explosive that could be easily controlled and transported.
3. Motivation behind the invention:
- Nobel's invention of dynamite was driven by his concern for the safety of workers in the mining industry.
- He wanted to create a safer alternative to the existing volatile explosives, such as nitroglycerin.
4. Impact of Dynamite:
- Dynamite revolutionized various industries by providing a reliable and safer explosive material.
- It made construction and mining activities more efficient and less risky.
- Nobel's invention played a significant role in the development of infrastructure worldwide.
5. Nobel Prize:
- Alfred B. Nobel's invention of dynamite brought him both fame and fortune.
- In his will, Nobel left his entire estate to establish the Nobel Prizes, including the Nobel Prize in Chemistry, Physics, Physiology or Medicine, Literature, and Peace.
In conclusion, Alfred B. Nobel, a Swedish chemist and inventor, invented dynamite in the late 1860s. His invention revolutionized various industries and brought him recognition worldwide.