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Introduction to science and the realm of physics, physical quantities, and units Read Online
1.1 Physics: an introduction Read Online
1.2 Physical quantities and units Read Online
1.3 Accuracy, precision, and significant figures Read Online
What is your first reaction when you hear the word “physics”? Did you imagine working through difficult equations or memorizing formulas that seem to have no real use in life outside the physics classroom? Many people come to the subject of physics with a bit of fear. But as you begin your exploration of this broad-ranging subject, you may soon come to realize that physics plays a much larger role in your life than you first thought, no matter your life goals or career choice.
For example, take a look at the image above. This image is of the Andromeda Galaxy, which contains billions of individual stars, huge clouds of gas, and dust. Two smaller galaxies are also visible as bright blue spots in the background. At a staggering 2.5 million light years from the Earth, this galaxy is the nearest one to our own galaxy (which is called the Milky Way). The stars and planets that make up Andromeda might seem to be the furthest thing from most people’s regular, everyday lives. But Andromeda is a great starting point to think about the forces that hold together the universe. The forces that cause Andromeda to act as it does are the same forces we contend with here on Earth, whether we are planning to send a rocket into space or simply raise the walls for a new home. The same gravity that causes the stars of Andromeda to rotate and revolve also causes water to flow over hydroelectric dams here on Earth. Tonight, take a moment to look up at the stars. The forces out there are the same as the ones here on Earth. Through a study of physics, you may gain a greater understanding of the interconnectedness of everything we can see and know in this universe.
Think now about all of the technological devices that you use on a regular basis. Computers, smart phones, GPS systems, MP3 players, and satellite radio might come to mind. Next, think about the most exciting modern technologies that you have heard about in the news, such as trains that levitate above tracks, “invisibility cloaks” that bend light around them, and microscopic robots that fight cancer cells in our bodies. All of these groundbreaking advancements, commonplace or unbelievable, rely on the principles of physics. Aside from playing a significant role in technology, professionals such as engineers, pilots, physicians, physical therapists, electricians, and computer programmers apply physics concepts in their daily work. For example, a pilot must understand how wind forces affect a flight path and a physical therapist must understand how the muscles in the body experience forces as they move and bend. As you will learn in this text, physics principles are propelling new, exciting technologies, and these principles are applied in a wide range of careers.
In this text, you will begin to explore the history of the formal study of physics, beginning with natural philosophy and the ancient Greeks, and leading up through a review of Sir Isaac Newton and the laws of physics that bear his name. You will also be introduced to the standards scientists use when they study physical quantities and the interrelated system of measurements most of the scientific community uses to communicate in a single mathematical language. Finally, you will study the limits of our ability to be accurate and precise, and the reasons scientists go to painstaking lengths to be as clear as possible regarding their own limitations.
Question: Which sport has a primary focus on muscular power?
Choices:
weight lifting
tennis
Rugby
Footbal
Question: The 50 meter sprint test can indicate an athletes
Choices:
balance
power
speed
agility
Question: The bodies ability to change direction at speed is called?
Choices:
speed
muscular power
agility
coordination
Question: The ability of the heart, blood, blood vessels, and the respiratory system to supply oxygen and necessary fuel to the muscles during exercise is called:
Choices:
Health-related fitness.
Skill-related fitness.
Physical fitness.
Cardiovascular fitness
Question: An appropriate exercise to develop abdominal muscular endurance would be?
Choices:
push-ups
sit-ups
chin-ups
pull-ips
Question: Muscular endurance is the ability to exert a single maximal contraction.
Choices:
True
False
Question: To improve muscular endurance an athlete should do?
Choices:
high repetitions with heavy weights
Low repetitions with heavy weights
high repetitions with light weights
low repetitions with light weights
Question: What component of fitness would be required for the splits or high kick?
Choices:
Muscular Endurance
Flexibility
Speed
Coordination
Question: A test that can indicate ones muscular power is?
Choices:
The sit up test
Standing long jump
The beep test
40-m sprint
Question: The health-related components of physical fitness are most associated with:
Choices:
How fast you improve.
How well the systems of the body operate.
How well you perform in sports activities.
Your level of athletic ability.
Question: Which one is NOT a component of fitness?
Choices:
Weight training
Balance
Co-ordination
Balance