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Fuel cell

A fuel cell is a device that converts chemical energy into electrical energy in a reaction in which hydrogen is oxidized to produce water.
Fuel cells have less heat loss, making them more energy-efficient than conventional fuel systems.
The fuel cell consists of a fuel electrode(-) for supplying hydrogen, an air electrode(+) for supplying oxygen, and an electrolyte between the two electrodes.

The only substance emitted by the fuel cell is water. Therefore, fuel cells(not like fossil fuels) do not emit carbon dioxide, making them environmentally friendly. Besides, little noise is produced when producing electricity.
However, fuel cells' commercialization requires various technical problems such as electrode material development, mass production, storage, and transportation of hydrogen.

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A fuel cell is a device that converts chemical energy into electrical energy in a reaction in which hydrogen is oxidized to produce water. Fuel cells have less heat loss, making them more energy-efficient than conventional fuel systems. The fuel cell consists of a fuel electrode(-) for supplying hydrogen, an air electrode(+) for supplying oxygen, and an electrolyte between the two electrodes.

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The photographs of the Earth and the moon close together that you can see on posters, etc., are designed to be easy to see.
The moon's apparent diameter is only about 0.5˚. This tells us that the Earth and the Moon are pretty far apart than you thought.
With the above simulation, explore how far the moon is.

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Real Size & Orbit of Earth and Moon - Javalab

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The photographs of the Earth and the moon close together that you can see on posters, etc., are designed to be easy to see. The moon's apparent diameter is only about 0.5˚. This tells us that the Earth and the...

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Eratosthenes' Calculation of Earth's Circumference

The first person to measure the earth's size was Eratosthenes, an ancient Greek scientist about 2,000 years ago.
Eratosthenes lived in Alexandria, near the Nile River's mouth by the Mediterranean coast, in northern Egypt. He knew that on a certain day each year, the Summer Solstice, in the town of Syene in southern Egypt, there was no shadow at the bottom of a well. He realized that he could determine how far away from directly overhead the Sun was in Alexandria by measuring the angle formed by a shadow from a vertical object.
He measured the shadow's length of a tall tower in Alexandria and used simple geometry to calculate the angle between the shadow and the vertical tower. This angle turned out to be about 7.2 degrees. Next, Eratosthenes used a bit more geometry to reason that the shadow's angle would be the same as the angle between Alexandria and Syene as measured from the Earth's center. And he found that the distance from Alexandria to Syene is about 925 km. Therefore, assuming that the earth is perfectly spherical, he used the principle that the center angle and the arc's length are proportional to each other in the circle.

7.2˚ : 925km = 360˚ : Earth's Circumference

He calculated the circumference of the earth at about 46,000 km. This value is slightly larger than today's measured value of about 40,075 km, but it is very accurate with the measurement technology at that time.

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Eratosthenes' Calculation of Earth's Circumference 2 - JavaLab

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The first person to measure the earth's size was Eratosthenes, an ancient Greek scientist about 2,000 years ago. Eratosthenes lived in Alexandria, near the Nile River's mouth by the Mediterranean coast, in northern Egypt. He knew that on a certain day each year, the Summer Solstice, in the town of Syene in southern Egypt, there was no shadow at the bottom of a well.

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Igneous rocks are rocks formed from molten magma. The material is made liquid by the heat inside the Earth's mantle.
Igneous rock occurs in two ways.

Slow cooling:
Igneous rock formed from magma that has become solid inside the earth is called intrusive igneous rock. Examples of intrusive igneous rock types are gabbro, diorite, and granite.

Fast cooling:
Igneous rock formed from lava that has become solid outside of the Earth is called extrusive igneous rock. This can happen because of the eruption of a volcano. Some extrusive igneous rock types are basalt, andesite, rhyolite, tuff, obsidian, and pumice.

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Classification of igneous rocks - JavaLab

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Igneous rocks are rocks formed from molten magma. The material is made liquid by the heat inside the Earth's mantle. Igneous rock occurs in two ways. Slow cooling: Igneous rock formed from magma that has become solid inside the earth is called intrusive igneous rock.

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About this simulation, When you press the button, you can see the corresponding strata. Combining the layer, you can create a variety of stratum. This simulation is presented as a mathematical model. Actual strata may be different.

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Continental Drift (Continental Drift Theory) - Javalab

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Move the continents to create a connected supercontinent (Pangea).

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How do greenhouse gases affect the climate? Explore the atmosphere during the ice age and today. What happens when you add clouds? Change the greenhouse gas concentration and see how the temperature changes.

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greenhouse effect free online simulations

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greenhouse effect free online animations

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Simulaciones de efecto invernadero online gratis * STEM OnLine

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Simulaciones interactivas online gratis sobre el efecto invernadero | Radiación | Gases de efecto invernadero ☝️¡Aprende o enseña diferente!

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Earth looked very different long ago. Search for addresses across 750 million years of Earth's history.

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Tectonic Explorer (GEODE Plate Tectonics Version)

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Set up a test planet with the Planet Wizard, selecting number of plates, density, and plate motion. Explore how movement on one side of a plate affects movement on the other side.

Make 3D cross-sections to explore how tectonic plates interact with each other below the surface. Run experiments to test how various features of Earth could have formed.

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Mapas del tiempo con el pronóstico de viento para Argentina. Previsión de viento para 14 días. Previsión para Argentina

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Green roof energy calculator - Urban Climate Research Center

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Fundado en 2002 por el ganador del Premio Nobel Carl Wieman, el proyecto de simulaciones interactivas de PhET de la Universidad de Colorado en Boulder crea simulaciones interactivas gratuitas de matemáticas y ciencias. Las simulaciones de PhET se basan en investigación educativa extensiva e involucran a los estudiantes mediante un ambiente intuitivo y similar a un juego, en donde aprenden explorando y descubriendo.