Earth receives a spectrum of electromagnetic radiation from the Sun which peaks in the visible range. Some of this light makes it to Earth's surface and is absorbed. The absorbed light is converted to thermal vibrations of charged particles, which then radiate infrared light. Greenhouse gases in the atmosphere (including carbon dioxide, methane, and water vapor) absorb the infrared light and then re-emit it in random directions. Some escapes to space, and some remains trapped in the atmosphere. The greenhouse effect keeps Earth warm enough to be habitable. However, human activities are increasing greenhouse gas concentrations and are thereby affecting Earth's climate system. Solutions to this problem include solar, wind, and nuclear energy, which do not emit greenhouse gases during operation.
00:00 - Intro
00:44 - Greenhouse effect overview
05:05 - Solar spectrum at the top and bottom of atmosphere
07:59 - Why do greenhouse gases absorb infrared light?
11:21 - Increasing greenhouse gases and climate change
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Khan Academy is a nonprofit organization with the mission of providing a free, world-class education for anyone, anywhere. Khan Academy has been translated into dozens of languages, and 15 million people around the globe learn on Khan Academy every month. As a 501(c)(3) nonprofit organization, we would love your help!
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,online learning,online class,video class,video tutorial,online education,TonUa-uB8hY,UC4a-Gbdw7vOaccHmFo40b9g, Knowledge, channel_UC4a-Gbdw7vOaccHmFo40b9g, video_TonUa-uB8hY,EdTech Literacy expert Sarah Robertson (Former CommonLit, now Product Leader at Khan Academy) gives a small group of District Administrators a deep dive into how technologists in Silicon Valley are working shoulder to shoulder with educators to solve age-old problems in the ELA classroom with AI. The focus of this webinar is the evolution of Khan Academy's Writing Coach tool for students and the newly released Teacher view. Sarah also shares some free Khanmigo AI tools that are useful for ELA teachers.
Learn more at districts.khanacademy.org
,1,Courses on Khan Academy are always 100% free. Start practicing—and saving your progress—now! https://www.khanacademy.org/science/highschool-physics/x6679aa2c65c01e53:motion-and-forces/x6679aa2c65c01e53:forces/v/intro_to_forces_1
A force is a push or pull. There are several types, including: applied (from person or machine), tension (from string or cable), gravity (between masses), normal (perpendicular to surface), friction (moving across a surface), thrust (from pushing something the other way), drag (resistance from air or other fluid), buoyancy (from displacing a fluid), and lift (on wings moving through air).
Sections:
00:00 - Intro
00:20 - Applied force and tension
01:15 - Gravity and normal force
02:40 - Friction
03:41 - Thrust
04:29 - Drag force (air resistance)
05:40 - Buoyant force
07:25 - Lift
08:50 - Summary
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Khan Academy is a nonprofit organization with the mission of providing a free, world-class education for anyone, anywhere. Khan Academy has been translated into dozens of languages, and 15 million people around the globe learn on Khan Academy every month. As a 501(c)(3) nonprofit organization, we would love your help!
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Volunteer here: https://www.khanacademy.org/contribute?utm_source=youtube&utm_medium=desc
,1,Acceleration is the rate of change of velocity (a = Δv/Δt). The unit for acceleration is m/s/s, or m/s^2. Acceleration is a vector with magnitude and direction. If velocity and acceleration point the same direction, the object is speeding up. If velocity and acceleration point opposite directions, the object is slowing down. Changing direction is also a form of acceleration.
Sections:
00:00 - Visualizing acceleration (Who wins the race?)
01:11 - What is acceleration?
02:54 - Acceleration can be tricky!
04:21 - Oil drop diagram and acceleration direction
07:40 - Acceleration when velocity is constant?
08:40 - Acceleration when speed is constant?
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Khan Academy is a nonprofit organization with the mission of providing a free, world-class education for anyone, anywhere. Khan Academy has been translated into dozens of languages, and 15 million people around the globe learn on Khan Academy every month. As a 501(c)(3) nonprofit organization, we would love your help!
Donate here: https://www.khanacademy.org/donate?utm_source=youtube&utm_medium=desc
Volunteer here: https://www.khanacademy.org/contribute?utm_source=youtube&utm_medium=desc
,1,An object's position specifies how far the object is from a reference point, and in what direction. The rate than an object's position changes is called velocity. Average velocity is calculated as change in position divided by change in time. Position and velocity are vector quantities. Average speed is calculated as distance travelled divided by time. Speed and distance are scalar quantities with no direction.
Sections:
00:00 - What is position?
02:31 - What are vectors?
03:31 - What is velocity?
05:03 - Visualizing velocity
07:01 - What is speed?
09:06 - Difference between speed and velocity
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Khan Academy is a nonprofit organization with the mission of providing a free, world-class education for anyone, anywhere. Khan Academy has been translated into dozens of languages, and 15 million people around the globe learn on Khan Academy every month. As a 501(c)(3) nonprofit organization, we would love your help!
Donate here: https://www.khanacademy.org/donate?utm_source=youtube&utm_medium=desc
Volunteer here: https://www.khanacademy.org/contribute?utm_source=youtube&utm_medium=desc
,1,Earth receives a spectrum of electromagnetic radiation from the Sun which peaks in the visible range. Some of this light makes it to Earth's surface and is absorbed. The absorbed light is converted to thermal vibrations of charged particles, which then radiate infrared light. Greenhouse gases in the atmosphere (including carbon dioxide, methane, and water vapor) absorb the infrared light and then re-emit it in random directions. Some escapes to space, and some remains trapped in the atmosphere. The greenhouse effect keeps Earth warm enough to be habitable. However, human activities are increasing greenhouse gas concentrations and are thereby affecting Earth's climate system. Solutions to this problem include solar, wind, and nuclear energy, which do not emit greenhouse gases during operation.
00:00 - Intro
00:44 - Greenhouse effect overview
05:05 - Solar spectrum at the top and bottom of atmosphere
07:59 - Why do greenhouse gases absorb infrared light?
11:21 - Increasing greenhouse gases and climate change
------------------
Khan Academy is a nonprofit organization with the mission of providing a free, world-class education for anyone, anywhere. Khan Academy has been translated into dozens of languages, and 15 million people around the globe learn on Khan Academy every month. As a 501(c)(3) nonprofit organization, we would love your help!
Donate here: https://www.khanacademy.org/donate?utm_source=youtube&utm_medium=desc
Volunteer here: https://www.khanacademy.org/contribute?utm_source=youtube&utm_medium=desc
