NOVA

Great Human Odyssey | Early Boat Technology

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Learn about the development of ancient Polynesian ship technology, from dugout canoes to catamarans, in this video from NOVA: Great Human Odyssey. Although there is no archeological evidence of the earliest boats, there are clues in Papua New Guinea, where people are still crafting dugout canoes like their ancestors did. War canoes were long and fast, functioning best in calm waters. To venture out into the ocean, the Papuans added an outer rig to widen and stabilize the vessel so that it would not be tipped by the waves. With an added sail, these outriggers could move easily and swiftly between islands, allowing the people to settle the southern Pacific. Wind tunnel tests on a model of an ancient Polynesian vessel show how it could sail into the wind. The subsequent development of the catamaran—basically two canoes attached together with a large deck—allowed for further expansion across the ocean. This resource is part of the NOVA Collection.

A Green Way to Fight Fires

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Learn about TetraKO™, an environmentally friendly firefighting product, in this video from NOVA: “Making Stuff Safer.” Host and technology columnist David Pogue meets with the engineers who designed TetraKO™ to learn how the cornstarch-based gel works as an effective fire suppressant and retardant. The product is a non-Newtonian fluid, which means that it has special properties. When it is first sprayed from a hose, it is liquid. Once it lands on a surface, it turns into a solid and adheres to that surface. In addition, because it is nontoxic, it is safer for firefighters and wildlife than existing chemical fire suppressants and retardants.

This video is available in both English and Spanish audio, along with corresponding closed captions.

Making Boats Fly

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Learn how advances in technology allow boats to go faster than ever before in this video from NOVA: “Making Stuff Faster.” Host and technology columnist David Pogue examines two factors that limit speed—energy and resistance—and describes how Oracle Team USA maximizes the speed of its boat. Instead of a traditional sail, the boat has a rigid carbon-fiber wing that acts as an airfoil to create lift and propel the boat forward. In addition, foils on the underside of the boat lift it largely out of the water, which reduces the drag force exerted by the water on the boat.

This video is available in both English and Spanish audio, along with corresponding closed captions.

Breaking Point: Testing Tensile Strength

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In this video excerpt from NOVA’s "Making Stuff: Stronger", host and New York Times technology columnist David Pogue visits DuPont™, where Kevlar® was invented. After learning how this bulletproof material is made, David puts its strength to the test with an ice pick. A related demonstration tests and compares the tensile strength and elasticity of Kevlar®, nylon, steel, and cotton thread by using them to lift weighted buckets. Students learn that materials can be strong in different ways—some have high tensile strength, others are more elastic—and that materials scientists test the strength of materials by stressing them to their breaking point.

Search for the Super Battery | Comparing Grid Energy Storage Solutions

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Examine three different technologies to store energy from renewable or conventional power sources for later use on an electrical grid, in this video from NOVA: Search for the Super Battery. With the means to currently store just 2 percent of its generating capacity, the United States is searching for efficient and economical energy-storage solutions. One option is to store energy in a massive spinning flywheel that generates electricity as it slows. Other current storage solutions include pumped hydroelectric storage and lithium-ion batteries. Each has benefits and limitations for managing energy on the nation’s electrical grid. This resource is part of the NOVA Collection.

Powering Torque in the Trunk

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Learn about the technology behind the White Zombie, an extremely fast electric car, in this video from NOVA: “Making Stuff Faster.” Host and technology columnist David Pogue explores how torque affects the acceleration of a car and how the White Zombie compares to other automobiles. For John Wayland, the creator of the White Zombie, the biggest challenge was finding a battery that could power the car’s remarkable motor. Wayland took inspiration from the way a helicopter operates and develop a lithium and manganese battery pack that allows the car to go fast and far. 

Antarctica: Sea Ice

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Each winter, the ice apron that surrounds the continent of Antarctica expands from its summertime area of about 4 million square kilometers (1.5 million sq mi) to 20 million square kilometers (7.5 million sq mi). Although its presence has proven treacherous for would-be explorers and commercial shippers, sea ice provides essential hunting, feeding, and breeding habitats to polar bears, seals, and penguins. It also helps regulate temperature, moisture, and ocean salinity worldwide. In this video segment adapted from NOVA, learn how sea ice forms and how its seasonal fluctuation dramatically changes the continent of Antarctica.

The Grand Canyon: The Top Two Rock Layers

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As you look at the sedimentary rocks at the Grand Canyon's rim, the top layers of visible rock are the youngest. In this video segment adapted from NOVA, a scientist explains what we know about the changing conditions in this location and the kinds of life they supported. The canyon's top layer, the Kaibab formation, records deposits laid down at the bottom of a shallow sea. The Coconino sandstone formation below it indicates that these watery conditions were preceded by much drier ones.

This video is available in both English and Spanish audio, along with corresponding closed captions.

A Strange New Planet

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Scientists have been looking for extra-solar planets for decades, but only recently, with better equipment and improved techniques, have they finally unveiled new and unusual planets. Since 1995, over 155 planets have been discovered orbiting stars other than our Sun. In this video segment adapted from NOVA, two of the most successful planet-hunters discuss the search for extra-solar planets.

The Electromagnetic Spectrum

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In this video from NOVA’s Sun Lab, examine how scientists use electromagnetic radiation to learn about the Sun. The process of nuclear fusion in the core of the Sun produces energy in the form of electromagnetic radiation, or light. The wavelength of photons (particles that carry electromagnetic energy) depends on how much energy the photons carry. The Sun emits energy at a range of wavelengths; however, until recently, human observations of the Sun were limited to the narrow visible range. Advances in technology have allowed humans to make observations across the electromagnetic spectrum that have revealed the dynamic nature of the Sun.

This video is available in both English and Spanish audio, along with corresponding closed captions.

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