Write a biographical essay on one of the physicists listed below. Your biography must include a description of the significant contribution to science made by the physicist you selected. Stephen Hawking (1942 - 2018)

Answer:

See below

Step-by-step explanation:

Galileo Galilei: The Father of Modern Physics

Galileo Galilei was an Italian physicist, mathematician, and astronomer who is widely regarded as the father of modern physics. He was born on February 15, 1564, in Pisa, Italy. His father, Vincenzo Galilei, was a musician, while his mother, Giulia Ammannati, was from a noble family. Galileo was the first of six children and grew up in a household that valued education and intellectual curiosity.

Galileo received his early education at a Jesuit monastery, where he learned Latin, Greek, and mathematics. He was later sent to the University of Pisa to study medicine, but he soon became interested in mathematics and physics. In 1589, he was appointed as a professor of mathematics at the University of Pisa.

In 1609, Galileo invented the telescope and used it to observe the sky. He discovered that the Moon had craters, that Jupiter had moons orbiting it, and that Venus went through phases like the Moon. These discoveries supported the heliocentric model of the solar system, which had been proposed by Nicolaus Copernicus in the 16th century. Galileo's observations and discoveries challenged the geocentric model of the solar system, which had been the prevailing model since ancient times.

In 1610, Galileo published a book called "Sidereus Nuncius," or "Starry Messenger," which described his observations of the Moon, Jupiter, and the stars. The book made him famous throughout Europe, but it also brought him into conflict with the Catholic Church, which opposed the heliocentric model of the solar system. Galileo was accused of heresy and put on trial in 1633. He was found guilty and spent the rest of his life under house arrest.

Galileo's contributions to science were not limited to astronomy. He also made significant contributions to the field of mechanics. He was the first to demonstrate that objects of different masses fall at the same rate when dropped from the same height. He also developed the law of inertia, which states that an object at rest will remain at rest unless acted upon by an external force.

Galileo's work in mechanics and astronomy laid the foundation for the modern scientific method. He believed in the importance of observation, experimentation, and mathematical analysis in the pursuit of scientific knowledge. He also believed in the importance of skepticism and critical thinking in the evaluation of scientific theories.

Galileo's legacy can be seen in the work of many of the great scientists who followed him, including Isaac Newton and Albert Einstein. His contributions to science continue to be celebrated and honored today, and he remains one of the most influential figures in the history of science.

Galileo's significance to science is not limited to his contributions to astronomy and mechanics. His work also had a profound impact on the relationship between science and religion. Galileo's conflict with the Catholic Church was not just a dispute over the heliocentric model of the solar system. It was a clash between two different ways of looking at the world. The Church believed that the Earth was the center of the universe and that human beings were at the center of God's plan. Galileo's work challenged this view, and in doing so, it challenged the authority of the Church.

Galileo's trial and condemnation by the Church were not just a setback for science. They were also a setback for human freedom and intellectual curiosity. Galileo's story is a reminder that the pursuit of scientific knowledge is not always easy or straightforward, and that it can sometimes come into conflict with powerful institutions and entrenched beliefs. Galileo's courage in standing up for his beliefs, despite the risks, is an inspiration to all those who seek to challenge the status quo and push the boundaries of knowledge.

In conclusion, Galileo Galilei was a true pioneer in the field of physics and astronomy. His observations and discoveries changed the way we understand the universe, and his contributions to the field of mechanics laid the foundation for modern physics. Galileo's legacy continues to be celebrated and honored today, and his story serves as a reminder of the importance of intellectual curiosity, skepticism, and critical thinking in the pursuit of scientific knowledge. Despite the challenges and setbacks he faced, Galileo never lost his passion for science and his belief in the power of human reason. His work will continue to inspire future generations of scientists and thinkers for centuries to come.

Answer:

Essay given below.

Step-by-step explanation:

Nikola Tesla: A Genius in Electrical Engineering and Physics

Nikola Tesla was a Serbian-American inventor, electrical engineer, mechanical engineer, and physicist, widely regarded as one of the most important figures in the history of science and technology. He was born on July 10, 1856, in Smiljan, Croatia, and died on January 7, 1943, in New York City, USA. Tesla made numerous significant contributions to the field of electrical engineering and physics, and his work paved the way for the development of modern technology.

Early Life and Education

Tesla was born into a family of Serbian ethnicity in Smiljan, Croatia. His father was an Orthodox priest and his mother was a homemaker. Tesla had a great love for science and technology from a young age. He was fascinated by the workings of mechanical devices and would often spend hours studying them.

Tesla received his primary education in Smiljan before moving to Karlstadt, Austria, to attend high school. He continued his education in Prague, where he studied physics and mathematics at Charles-Ferdinand University. After completing his studies, Tesla moved to Budapest, where he began working as an assistant to a telegraph engineer.

Early Career

In 1881, Tesla moved to the United States to work with Thomas Edison, one of the leading inventors of the time. Tesla was hired to work at Edison Machine Works, where he was tasked with improving Edison's DC generator. However, Tesla's vision for the future of electricity differed greatly from Edison's. Tesla believed that alternating current (AC) was superior to direct current (DC), which was favored by Edison.

Despite the controversy, Tesla continued to work on his own projects and eventually established his own laboratory. He developed a complete system of AC generators, transformers, and motors that allowed electricity to be transmitted over long distances efficiently. Tesla's AC system revolutionized the field of electrical engineering and made it possible to distribute electricity over long distances.

AC and Electrical Engineering

Tesla's work on alternating current had a significant impact on the field of electrical engineering. His development of the AC motor made it possible to power a wide range of electrical devices, from household appliances to large industrial machinery. Tesla's AC system was also instrumental in the development of the modern power grid, which allows electricity to be distributed over long distances and to be used by millions of people.

In addition to his work on AC, Tesla also made significant contributions to the field of physics. He conducted numerous experiments on high-frequency electricity and made several important discoveries, including the concept of resonance. Tesla also proposed several theories about the nature of light and electromagnetic radiation.

Tesla Coil

One of Tesla's most famous inventions was the Tesla Coil, which he developed in the 1890s. The Tesla Coil is a high-voltage transformer that produces a high-frequency, high-voltage current. It is used in a wide range of applications, from radio and television broadcasting to medical devices.

The Tesla Coil is made up of a primary and secondary coil, with a spark gap between them. When the primary coil is charged with electricity, it produces a magnetic field that induces a high-voltage current in the secondary coil. This produces a stream of high-voltage sparks that can be used for a wide range of applications.

Wireless Communication

Tesla was also known for his visionary ideas about technology and the future. He predicted the development of wireless communication a the efficient transmission of energy and information. Tesla conducted numerous experiments to demonstrate the feasibility of his wireless communication system, and even built a laboratory on Long Island, New York, called Wardenclyffe Tower, to further his research. Although the project was ultimately unsuccessful due to funding issues, Tesla's work on wireless communication laid the foundation for modern telecommunications technology.

Later Life and Legacy

In his later years, Tesla continued to work on a wide range of projects, including robotics and renewable energy sources. However, he struggled financially and was largely forgotten by the scientific community. Despite this, Tesla remained passionate about his work and continued to innovate until his death in 1943.

Today, Tesla's contributions to science and technology are widely recognized, and he is regarded as one of the most important figures in the history of electrical engineering and physics. His work on alternating current and wireless communication paved the way for the development of modern technology, and his visionary ideas continue to inspire scientists and engineers today.

Conclusion

Nikola Tesla was a genius in the fields of electrical engineering and physics, and his work had a significant impact on the development of modern technology. Tesla's contributions to the field of electrical engineering, including his development of the AC system and the Tesla Coil, revolutionized the way that electricity is generated and transmitted. His visionary ideas about wireless communication laid the foundation for modern telecommunications technology, and his work on high-frequency electricity and resonance contributed to our understanding of the nature of light and electromagnetic radiation.

Despite struggling financially and being largely forgotten by the scientific community in his later years, Tesla's legacy lives on today. His innovations and ideas continue to inspire scientists and engineers, and his contributions to science and technology will always be remembered.

Answer:

Option D

Step-by-step explanation:

D.
Heat each cube to the same temperature, place each cube into different containers with 500 grams of water at the same temperature, and measure the temperature of the water.

Answer:
7.25 secs.

Explanation:
First find the distance it takes to stop
s = [v^2-u^2]/2a = 0^2 - 8.7^2/2[-2.4] = 8.7^2/4.8
Next find the time it takes to go that distance , s = ut +[1/2] at^2
8.7^2/4.8 = 8.7t +[1/2] [ -2.4]t^2 , rearrange and
t^2 -[8.7/1.2]+ 8.7^2/[(1.2)(4.8)]=0 complete the square
[t - (8.7/2.4)]^2=0
t = 8.7/2.4 = 3.625 secs
At this stage the deceleration will push the object back in the direction it came from for another 3.625 secs when it will be 8.7 m/s again
Total time , T =2t = 7.25 secs.

Note:
The term differential is used in calculus to refer to an infinitesimal (infinitely small) change in some varying quantity. For example, if x is a variable, then a change in the value of x is often denoted Δx (pronounced delta x). The differential dx represents an infinitely small change in the variable x.

The change in temperature is 9.52°CExplanation:Since, the heat supplied by the electric kettle is totally used to increase the temperature of the water.Thus, from the law of conservation of energy can be stated as:Heat Supplied by Electric Kettle = Heat Absorbed by WaterHeat Supplied by Electric Kettle = m C ΔTwhere,Heat Supplied by Electric Kettle = 20,000 JMass of water = m = 0.5 kgSpecific Heat Capacity of Water = C = 4200 J/kg.°CChange in Temperature of Water = ΔTTherefore,20,000 J = (0.5 kg)(4200 J/kg.°C) ΔTΔT = 20,000 J/(2100 J/°C)ΔT = 9.52°C

Weight of barbell (m) = 100 kg
Uplifted to height (h) = 2m
Time taken= 1.5 s
Work done by Jordan = potential energy stored in barbell = mgh
= 100×2×9.8
= 1960J
Power = energy/time
= 1960/1.5
1306.67watts

The horizontal and vertical motions of balloons are independent from each other.
Let vertical component of initial velocity U' horizontal component of initial velocity U"
Time of landing (t) is found with the help of vertical motion.
Since vertical component of initial velocity of balloon is zero(U' = 0)
From equation h = U't + 1/2gt^2
h = 1/2gt^2
t = √(2h/g)
t = √( 2×150/9.8)
t = 5.53 sec
Horizontal velocity = 50m/s
Horizontal range of balloon, R = U"t
= 50× 5.53
= 27.65m
So the balloon will go 27.65 metre away from the bridge

Gravity acceleration (g) = 9.8m/s^2
Time (t) = 3sec
Acceleration = velocity/time
Velocity = acceleration×time
= 9.8×3
= 29.4m/s

Initial velocity (u) = 0
Time taken = 4.5 seconds
Gravitational acceleration (g) = 9.8m/s^2
By the second equation of motion under gravity,
The distance that object fell down (h)
h = ut + (1/2)gt^2
h = 0×4.5 + (1/2)×9.8×(4.5)^2
h = 99.225 m

Convection occurs when the water becomes less dense and rises to the top as it warms, creating convection currents. When heater warms up the water around it, the water rises to the top and displaces cooler water, which is denser so it sinks lower.