Physics, 11th grade, Nelson
University preparation program
Unit 1. Kinematics.
Focus on STSE
Sports in Motion
The interactions among Science, Technology, Society, and the Environment (STSE) make
physics relevant to our lives in a million different ways. Sports are just one example. In
Canada, hockey is more than just a game. For many, it’s an obsession! Hockey is an
exciting, fast-paced sport. You can watch players skate down the ice to score the next
goal, a defenceman skillfully deflecting the puck out of the opposition player’s control,
or a goaltender making a difficult glove save. Speed is a critical part of the game, from
racing to get to the puck to firing a shot past the goaltender.
Imagine hockey or any other sport without motion and speed—it would not be nearly
as entertaining. The rapid acceleration of the puck during a slapshot, the way that a
skilled player can rapidly change his or her speed and direction of motion—these highspeed
actions are what make a hockey game so exciting. In other sports, motion and
speed are just as important for the athlete as for the enjoyment of the fans. You can
clearly see the skill of professional athletes in the precision control of a long soccer pass,
or of a basketball as it sails through the air in a perfect jumpshot. There is a direct link
between how objects move and the level of excitement we experience while watching or
playing our favourite sports.
Chapter 1 - Motion in a Straight Line
What Effects do Moving objects Have on Society and the Environment?
Automobiles have been made in North America for over 100 years. As technology
has advanced, automobile designs have changed substantially. For
example, a 1909 Ford Model T could travel at a maximum speed of approximately
70 km/h. Th is was considered a frightening speed at the time. Over
time, vehicles have become faster. Today, many cars can reach speeds of 200 km/h
or more, much higher than the speed limits on any Canadian roads.
Scientists and engineers continue to develop a deeper understanding of
motion and the factors that aff ect it. Th is knowledge, coupled with technological
advances, has enabled them to produce extremely fast experimental
land vehicles. Th e Th rustSSC (SuperSonic Car) reached an astounding speed
of 1228 km/h. Th is extraordinary British-built vehicle was driven by a Royal
Air Force pilot and powered by two jet engines. The team that built the
ThrustSSC and other competing groups are now attempting to build even
faster vehicles.
Although we benefi t greatly from motor vehicles that transport huge
amounts of goods daily and make travel much easier, we now realize that
burning large amounts of fossil fuels has a negative impact on our environment.
Fuel consumption for the Th rustSSC was a mind-boggling 55 L of gasoline per
kilometre. In comparison, the passenger vehicles you see on the street consume
about 0.07 L/km. Many researchers have turned their attention to producing
practical vehicles with a lower environmental impact.
Students at the University of Waterloo are moving the technology of passenger
vehicles away from fossil fuels altogether. Th ey have designed and constructed
a series of solar vehicles called Midnight Sun, which have reached speeds of
117 km/h. Th e team captured the world record for the longest journey by a
solar-powered car.
Faster, more effi cient vehicles are an important part of the future of transportation
in Canada. Today’s students are tomorrow’s scientists and engineers.
With a sound understanding of the physics of motion, we can improve today’s
transportation and environmental technologies to help protect our planet.
Chapter 2. Motion in Two Dimensions
How Are Two-Dimensional Motions Determined?
Throughout its history, Canada has been known for its vast wildlife population.
Global warming and human activity, however, have had a negative
impact on many of Canada’s wildlife species. The U.S. Geological Survey
predicts that by 2050 Canada’s polar bear population will be only one-third
of its current level. Scientists have turned to global positioning system
(GPS) technology to help them better understand the impact that climate
change is having on many species. GPS is a navigational system that was
originally created by the U.S. Department of Defense. It consists of a series
of satellites and ground stations that emit or relay signals that can be detected
by receivers on Earth. Th e precise position of each satellite and ground station
is known. A GPS receiver receives signals from multiple satellites or ground
stations. Th e GPS receiver uses their vector positions to triangulate its own
location anywhere on Earth’s surface to within a few metres.
GPS technology has allowed scientists to precisely track the migratory
routes of caribou, polar bears, wolves, and many other types of animals. Th e
Northwest Territories’ Central Arctic Wolf Project had been tracking a male
wolf named Brutus and his pack in their travels across Canada’s Ellesmere
Island. Regardless of weather conditions or the time of day, Brutus’s GPS
tracking collar sent position data to scientists every 12 h. On one trip the
pack was measured travelling 129 km in 84 h. From the data gathered, scientists
were able to determine when the pack was hunting successfully, tracking
herds, resting, and even when young wolves were being born. By analyzing
GPS data, scientists were also able to determine where and when Brutus was
eventually killed by a musk ox. By tracking animal movements, we can learn
more about how they use their natural habitat and how they are adapting to
environmental changes due to climate change. GPS technology applies concepts
related to motion in two dimensions. You will learn more about these
concepts in this chapter.
Я, кстати, ещё тут закачал канадский учебник физики от 2002 года. Там всей этой тошноты, естественно, нет, и школьникам рассказывают с первых строчек про физику, а не про канадских белых медведей. Ну ок, первая глава начинается с короткой мотивационной врезки о канадской космонавтке, но во-первых, во врезке куча технических подробностей (невесомость там, итд), а во-вторых вообще все эти вещи типа космоса и технических подробностей издатели нынче боятся как огня. От вводных слов никуда не убежать, видимо, так что первая глава обсуждает возможный полёт на Марс.
Ну или вот, "привязка к жизни" от 2002 года:
Motion in Our Lives
Everything in our universe is in a state of motion. Our solar system moves through space in the Milky Way Galaxy. Earth revolves around the Sun while rotating about its own axis. People, animals, air, and countless other objects move about on Earth’s surface. The elementary particles that make up all matter, too, are constantly in motion. Scientists call the study of motion kinematics, a word that stems from the Greek word for motion, kinema. (A “cinema” is a place where people watch motion pictures.) Uniform motion is a movement at a constant speed in a straight line. (It is presented in section 1.2.) However, most motions in our lives are classified as nonuniform, which means the movement involves changes in speed or direction or both. A roller coaster is an obvious example of such motion —it speeds up, slows down, rises, falls, and travels around corners.
В общем, не боялись они ещё 20 лет назад упоминать про космос, про научные применения науки же, про элементарные частицы. Не боялись делать учебник физики учебником о науке, а не об игре в хоккей и охране хомячков. Гнилота расползлась именно за два последние десятилетия.
no subject
Date: 2021-08-01 09:56 pm (UTC)И идиоты, и мерзавцы одновременно.
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Date: 2021-08-01 10:19 pm (UTC)no subject
Date: 2021-08-01 10:23 pm (UTC)no subject
Date: 2021-08-02 08:53 am (UTC)///
А тут вон норот грит, что наука — это скукотища, поэтому подавай им хомячков и прочее прикладное значение, понятное любому фермеру оборудованому здравым смыслом:
Я задумался как-то: а почему популяризаторские книжки в СССР заходили "на ура" — а современные скучные и незапиминающиеся?
поставил перед собой две книжки: СССРовскую и современну. Понял.
В СССР не писали о чистой науке. Речь всегда шла или о том как науку превратили в технологию — или о опытах и их конкретных результатах (которые скоро станут технологией)
то есть всё то что являлось неясным, противоречивым, и ПОКА двузначным — об этом не говорилось.
Вот есть лазер, он режет металл и считывает звук.
Вот спутники геопозиционирования, вся ихняя точность базируется не столько на триангуляции сколько на поправках, введенных теорией относительности. Если бы не теория относительности — то погрешность спутникового геопозиционирования была бы километры, а так — 10 сантиметров.
no subject
Date: 2021-08-02 01:44 pm (UTC)Мера ж во всём должна быть. Поясняющие примеры "из жизни" — вполне могут быть увлекательны и полезны, см. тот же отрывок от 2002 года. И технические примеры, хоть и не являющиеся наукой, всё же несут уйму важного научного содержания для неквалифицированного читателя. Но тут же они, суко, пишут, что есть прямая пропорциональность между кинематическим движением хоккейной шайбы и восхищением публики. Это ж полное проституирование науки.
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Date: 2021-08-02 01:56 pm (UTC)no subject
Date: 2021-08-02 02:24 pm (UTC)no subject
Date: 2021-08-02 07:15 pm (UTC)no subject
Date: 2021-08-02 01:05 pm (UTC)no subject
Date: 2021-08-02 01:59 pm (UTC)no subject
Date: 2021-08-02 02:16 pm (UTC)no subject
Date: 2021-08-02 04:10 pm (UTC)да, слыхали такое.
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Date: 2021-08-03 01:35 am (UTC)https://m.facebook.com/story.php?story_fbid=1848819218624321&id=100004887810496
no subject
Date: 2021-08-03 02:02 am (UTC)no subject
Date: 2021-08-03 09:13 pm (UTC)Как до скатывания в говно средний выпускник школы не выносил из школы почти ничего, так и сейчас не выносит.
При это до скатывания откуда-то самозарождались сильные выпускники, в количествах, достаточных для народного хозяйства и науки. Так и после скатывания они откуда-то самозародятся.
Не все же ваши толковые ребята завезены из Китая?
no subject
Date: 2021-08-04 03:12 am (UTC)При такой системе "сильным выпускникам" просто неоткуда взяться, придется брать перспективных выпускников с плохими знаниями и учить их в универе практически с нуля.
no subject
Date: 2021-08-04 06:12 pm (UTC)no subject
Date: 2021-08-05 09:39 pm (UTC)no subject
Date: 2021-08-06 01:19 pm (UTC)А учитель, в общем, может делать все, что захочет, если дети и их родители останутся довольны. Вполне могут найтись и такие, кому интереснее послушать про математику, а не про строительство вигвамов.