100's Day

What does 100 look like? Sound like? Feel like? In this video from Curious George, explore the many ways to measure 100 things.

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3D Space: Illusion or Reality?

This video excerpt from NOVA’s "The Fabric of the Cosmos: What Is Space?" reveals new data about black holes that has led to a new idea about the universe: Instead of everything being a three-dimensional object, it’s possible that everything is actually just a hologram.

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Accidental Discoveries

This segment from Swift: Eyes through Time traces the history military officers and engineers discovering a strange phenomenon in the sky that astronomers now know are gamma-ray bursts.

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Acids and Bases: Cabbage Juice Indicator

In this video segment, the ZOOM cast demonstrates how to use cabbage juice to find out if a solution is an acid or a base.

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Acids and Bases: Making a Film Canister Rocket

In this video segment, ZOOM cast members mix different amounts of baking soda and vinegar to see which combination produces the most carbon dioxide for launching a film-canister rocket.

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Acids and Bases: Testing Rocket Cars

In this ZOOM video segment, cast members make bottle rocket cars using lemon juice and baking soda, and experiment with different ways of launching the cars.

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Acids and Bases: Testing Rockets

What happens when you mix baking soda and lemon juice? Watch the ZOOM cast launch a rocket using kitchen chemistry.

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Airborne Wind Energy

The strongest and most consistent winds are found in the jet stream as high as 30,000 feet above the earth. In this video from QUEST produced by KQED, learn about the benefits and challenges of wind energy.

Air Power: Experimenting with Balloons

In this video segment adapted from ZOOM, cast members experiment with the amount of air expelled first from a balloon, then through a straw attached to it, and see how both affect a balloon's behavior.

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Air Power: Making a Hovercraft

In this video segment adapted from ZOOM, cast members make their own hovercraft and demonstrate how the air leaking out of a balloon can make a plastic plate hover above a table.

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Arch Bridge

This video segment adapted from Building Big illustrates the strength of the arch in bridge design and construction.

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Astronomy Theories

This video segment from Swift: Eyes through Time deals with the advancement of science through changing existing ideas, refuting outdated theories, and incorporating new findings.

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Atomic Arrangements in Solids

This video/animation asks the question "So if the same molecules are in the solid, liquid, and vapor forms of water, why are their properties so different?" The properties of a material are affected not just by the kinds of atom in it, but also by how they are arranged, and how free they are to move around. Forms of carbon are introduced, from graphite to buckyballs.

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Atomic Structure of an Alloy

Learn about the atomic structure of bronze, a copper alloy, in this video excerpt from NOVA: "Hunting the Elements."

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Atoms: The Space Between

This video segment adapted from A Science Odyssey takes a look at the scale of the atom and the tremendous amount of space between the electrons and the nucleus. If all this empty space exists in matter, how can any substance be solid?

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Balloon Brain: Designing a Helmet

In this video segment adapted from ZOOM, cast members are challenged to design protective headgear for a water balloon using what they know about the properties of the materials available.

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Basketball Physics

In this video from DragonflyTV, Jai and Jonathan track, graph, and analyze the motion of basketball shots as they investigate what factors influence the accuracy of their game.

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Bend, Twist and Break: Beyond the Laboratory

Dr. Chris Muhlstein explains that when scientists study fracture surfaces from controlled experiments to understand the resulting shapes and features, they can use their understanding to deduce what happened when they were not around to see the material fail or break. Further they can predict what will have to a larger or smaller piece of material under stress. This process is how scientists and engineers translate a lab experiment into a design for an airplane, bridge or even a bike frame.

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Bend, Twist and Break: Breaking Glass

Dr. Chris Muhlstein explains that researchers learn about the scientific basis for failure of materials by running experiments in the lab, using a simple shape like a glass rod to calculate the strength of material and predict its failure. The same tests can be done at the micro and nano scale using tiny specimens. Students can run a similar experiment with a bar of chocolate.

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Bend, Twist and Break: Fracture Surfaces

Dr. Chris Muhlstein explains that fracture surfaces can reveal how and why a material has failed. An image of a fracture surface has features or shapes that we can use to understand where a material failed and why. Scientists use an optical microscope or a scanning electron microscope to read a fracture surface at high magnifications, much like we read maps to find our way.

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Bend, Twist and Break: The Bridge

Dr. Chris Muhlstein explains that the arrangement of atoms in a material determines the properties. He drops an iPod to illustrate how the arrangement of atoms can protect it from damage; he narrates footage of the collapse of the Tacoma Narrows Bridge in the 1940s to show how the deformation of materials can cause the collapse of a structure.

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Beyond Einstein

NASA scientists describe some of the ways current science is addressing several of Einstein's fundamental questions and theories in this video adapted from NASA.

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Blacker Than Black

In this video adapted from NASA, two members of a NASA research team working to produce carbon nanotubes share some background behind this new technology, show examples of how it will be useful, and explain the various tests being performed to ensure readiness for spaceflight.

A Boat That Floats

In this video from Curious George, children build boats out of everyday materials and then predict and observe whether the boats sink or float.

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Booming Sands

This video segment, adapted from NOVA scienceNOW, presents basic concepts of physics behind "booming" sand dunes. See how surface tension affects potential and kinetic energy and how it all works together to create sound.

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Breathing Blue

In this demonstration of chemical change, the presenter blows breath into a methylene blue solution releasing carbon dioxide which acidifies the water and changes it from a bright blue color to green.

Bringing Down the Bolt

Learn about how lightening strikes in this video segment from Science Friday.

Building Curiosity: Rover Rocks Rocker-Bogie

NASA engineers test Curiosity, the Mars Science Laboratory rover, and demonstrate its material properties, its handling and mobility, and its design features in this NASA video.

Building Simple Machines: A Glass of Milk, Please

In this video segment adapted from ZOOM, the cast shows how the 34 steps in their Rube Goldberg invention use everything from gravity to carbon dioxide gas in order to accomplish one simple task: pouring a glass of milk.

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Building Simple Machines: Plant Quencher

In this video segment from ZOOM, Jillian explains how her simple machine uses marbles, levers, flowing sand, and a spinning wheel to water a plant.

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Building the Channel Tunnel

How do you build a tunnel 32 miles long -- under water? This video segment adapted from Building Big, follows the construction of the Channel Tunnel (nicknamed "Chunnel"), the engineering wonder that connects England to France.

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Calorimetry

Do you know how many calories are in a macadamia nut? This video segment highlighting a Calorimetry experiment will give you the answer.

Capturing Carbon

In this video segment adapted from NOVA scienceNOW, a scientist, inspired by his daughter's science fair project, develops a synthetic "tree" to remove excess carbon dioxide from the air.

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Carbon-Fiber Car of the Future

In this video segment adapted from NOVA, find out how cars made of a material stronger than steel and half the weight can help combat climate change.

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Carnival Physics: Midway Games

Follow Mary Jane and Eliza as they test and measure the best way to use a moving ball's energy to win at carnival games in this video from DragonflyTV.

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Center of Gravity: Pencil Balance

Watch the ZOOM cast learn about center of gravity by trying to balance a pencil on their fingers and noses.

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Centripetal Force

In this animation a ball bounces off the sides of the circle, and the number of sides double, until the circle appears to exert force on a ball that is constant in size and always directed towards the center.

Centripetal Force: Roller Coaster Loops

This video segment explains centripetal force and illustrates how roller coasters rely on it to give you a thrilling ride.

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Cheese: Not the Same Mold Story

In this video, Science Friday investigates the secret life of cheese.

The Chemistry of Makeup

In this video from DragonflyTV, join Jazi and Danielle as they experiment with different combinations of everyday ingredients in order to create and test batches of lip gloss.

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Citigroup Skyscraper Design Problem

This video segment adapted from Building Big looks at the challenges faced by structural engineer William LeMessurier in designing a new skyscraper and how he very closely averted disaster.

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Clean Coal?

Explore the challenges facing the deployment of clean coal technology in this video segment adapted from FRONTLINE: "Heat."

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Clifton Suspension Bridge

This video segment from Building Big illustrates the basic design principles of the Clifton Suspension Bridge in Bristol, England.

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Climate Watch: Unlocking the Grid

Today we rely on electricity more than ever. In this video from QUEST produced by KQED, explore the challenges of harnessing renewable energy.

Colliding Neutron Stars Create Black Hole and Gamma-ray Burst

This video from NASA describes the detailed computer modeling used to predict that colliding neutron stars can produce gamma-ray bursts similar to those associated with black holes.

Columns: Experimenting with Balloons

Watch the ZOOM cast find out how many balloons filled with air and then with water are required to support the weight of a cast member.

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Columns: Experimenting with Paper Cups

In this video segment from ZOOM, the cast experiments to see if a bunch of paper cups covered by a piece of cardboard can support the weight of a cast member.

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Columns: Finding the Strongest Shape

In this video segment, members of the ZOOM cast experiment by bending and folding sheets of paper into various shapes to see which shape will support the weight of a heavy book.

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Columns: Hillary's Neighborhood

In this video segment from ZOOM, Hillary, from Randolph, MA, takes us on a tour of the columns in her neighborhood.

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Conical Pendulum

A pendulum that swings in a horizontal circle and sweeps out the shape of a cone with its mass and string is known as a “conical pendulum.” In this animation we see the pendulum sweep from several angles with a superimposed equation toward the end.

Converting to Biodiesel

Meet a college student whose class project to turn cooking grease into diesel fuel resulted in converting bus fleets to biodiesel, in this video from Earth Island Institute's New Leaders Initiative.

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Cooking Cookies with Solar Power

In this video segment adapted from ZOOM, two solar cookers are tested against a control to see which can cook a "s'more" faster.

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Cosmic Origin Spectrograph

This video from NASA features the Cosmic Origin Spectrograph (COS), which allows scientists to use spectrographic analysis to assess the composition of intergalactic material.

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Counting Neutrons on the Moon

Find out how scientists are using a neutron detector onboard a satellite to try to find water on the Moon in this video adapted from NASA.

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Dark Energy

Dark energy makes up 70 percent of the universe. In this video from QUEST produced by KQED, meet one of the country's leading scientists who is trying to understand dark energy.

Defy Gravity! Balancing Balls on Air

In this video segment adapted from ZOOM, cast members use a hair dryer to balance a ball in a stream of air, seemingly defying gravity.

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Defy Gravity! Centripetal Force

How can you keep a ball from falling out of a jar if the jar is upside down? Watch the ZOOM cast use centripetal force to meet this challenge.

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Defy Gravity! Upside Down Ping Pong Ball

In this video segment, the ZOOM cast is challenged to keep a ping pong ball in a funnel while the funnel is held upside down, seemingly defying gravity.

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Density and Buoyancy: Experimenting with Club Soda

In this video segment adapted from ZOOM, the cast discovers that gas-filled bubbles act like life jackets for raisins, making them buoyant.

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Density and Buoyancy: Making Eggs Float

Why does an egg float in salt water? Learn about density and buoyancy in this video segment adapted from ZOOM.

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Density and Buoyancy: Mixing Hot and Cold Water

Watch warm water float on top of cold water in this video segment adapted from ZOOM.

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Density and Buoyancy: Pouring Air into Water

This video segment adapted from ZOOM offers a clever demonstration of buoyancy by showing how to pour a cup of air into a cup filled with water.

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Density and Buoyancy: Testing Liquids

Will a grape float in oil? Will a metal nut sink in corn syrup? Watch as the ZOOM cast tests the buoyancy of a variety of liquids and objects.

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The Deployable Energy Absorber

Watch how engineers stage a crash to test a new helicopter safety design technology in this video from NASA.

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Designing a Paper Bridge

In this video segment adapted from ZOOM, cast members make a bridge from a single piece of paper. Will it be strong enough to hold a hundred pennies?

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Designing a Puff Mobile

The air you exhale can power a puff mobile. Watch as the ZOOM cast races their air-powered designs to see which design features are the most successful.

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Designing a Roller Coaster

This video adapted from DESIGN SQUAD profiles Chris Gray, a mechanical engineer who uses his knowledge of energy transfer to design roller coasters.

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Designing a Roller Coaster

In this video segment adapted from ZOOM, the cast is challenged to design and test a roller coaster with loops, hills, and U-turns.

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Designing Balloon Cars

Can the air in a balloon power a car? Watch students from Weston, Massachusetts, demonstrate their balloon car designs in this video adapted from ZOOM.

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Designing Electric Circuits: Door Alarm

In this video segment adapted from ZOOM, cast members design and build door alarms using a variety of materials, including aluminum foil, batteries, and buzzers.

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Designing Electric Circuits: Steadiness Tester

In this video segment adapted from ZOOM, cast members discover that metal is a good conductor of electricity as they play the steadiness tester game.

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Designing Future Cities: Alternative Energy

In this video segment adapted from ZOOM, visit a class as they design a city of the future that will use solar, wind, and water power to fuel its economy.

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Designing the Citigroup Skyscraper

This video segment adapted from Thinking Big, Building Small shows how a structural engineer overcame the challenge of building New York's Citigroup skyscraper over a church.

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Design Squad: Sound

In this video segment adapted from Design Squad—a PBS TV series featuring high school contestants tackling engineering challenges—learn about the fundamentals of sound as student teams create percussive and stringed instruments for a local band.

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Design Squad: Suspension Bridge

In this video segment adapted from Design Squad—a PBS TV series featuring high school contestants tackling engineering challenges—students employ the concepts of tension and compression to build a suspension bridge without the aid of power tools.

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Design Squad: Truss Bridge

In this video segment adapted from Design Squad—a PBS TV series featuring high school contestants tackling engineering challenges—students employ the concepts of tension and compression as they build a truss bridge without the aid of power tools.

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Detecting Life on Other Planets

In this video from NOVA scienceNOW, learn how scientists detect potential signs of life on distant planets.

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Developing the Periodic Table

This video excerpt from NOVA: "Hunting the Elements" looks at how early chemists developed the periodic table of elements.

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Do Materials Get Tired? Creep

This video explains that materials will deform slowly or “creep” under the right conditions, when constant force is applied. “Strain” is illustrated with rubber bands and we learn that engineers can calculate creep strain as a function of time.

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Do Materials Get Tired? Fatigue

This video explains how the strength of a material can be measured in the laboratory and used to design structures, like bikes, airplanes, and even chairs. We see a controlled lab experiment that applies precise force to a paperclip until it breaks.

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Do Materials Get Tired? Intro

This video explains matter is made up of atoms that dictate the properties of materials. Mechanical engineers measure the stress a material can take until it breaks. Their ultimate goal is to make a material that will repair itself.

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Don't Mess with Mercury

Learn about the dangers of mercury in this short video from the U.S. Environmental Protection Agency.

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Down to the Core Challenge

In this video from Design Squad Nation, kids design and build devices that can extract a core sample from a potato “asteroid.” They also learn how samples give NASA scientists insight into solar system objects.

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Dust-Proofing a Mars Rover

Enter the lab of NASA scientist Dr. Carlos Calle to see how systems are being developed to keep planetary rover solar panels dust-free, in this video from NASA EDGE.

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Einstein's Cosmic Speed Limit

This video, adapted from NASA, presents rare experimental evidence from the Fermi Gamma-ray Space Telescope supporting Einstein's prediction that space-time is smooth.

Einstein's Special Theory of Relativity

What happens when you approach the speed of light? This video segment adapted from NOVA follows one of Albert Einstein's thought experiments and his quest to find the answer.

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Einstein's Thoughts on the Ether

Do light waves travel through the ether like waves on a lake travel through water? In this video segment adapted from NOVA, a young Albert Einstein grapples with this question while examining the speed of light.

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Electric Girl

Anna loves electricity. Watch her construct a homemade flashlight and show off her new, electrifying hairdo in this video segment from ZOOM.

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Electricity

This video segment from IdahoPTV's D4K explains some electrical vocabulary and follows the route of electricity from its generation to the home.

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The Electromagnetic Spectrum: FRONTLINE

This video segment adapted from FRONTLINE introduces the electromagnetic spectrum and explains how the various types of electromagnetic waves are distinguished by the amount of energy each wave carries.

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The Electromagnetic Spectrum: NASA

From radio waves to gamma rays, this video segment from NASA introduces the seven categories of the electromagnetic spectrum and how each type of radiation is part of our everyday lives.

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Electrophoresis and Gel Analysis

In this animation produced by WGBH and Digizyme, Inc., see how molecules of DNA are separated using gel electrophoresis, and how this process enables scientists to compare the molecular variations of two or more DNA samples.

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The Elements: Forged in Stars

The story of how elements from lithium to uranium are created by stars is illustrated through animation and a hands-on periodic table in this video segment adapted from NOVA.

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Energy Sources

Although California uses more renewable resources than many other states, much of the state's electricity still comes from nonrenewable sources. Find out how using renewable energy sources to create electricity helps reduce fossil fuel consumption and how it has the potential to have the largest impact on climate change.

Energy Sources

This video segment illustrates a variety of energy sources used to generate electricity, some of which are in use and some of which are under exploration.

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Energy Transfer in a Trebuchet

On NOVA, a team of carpenters, timber framers, engineers, and historians recreate a medieval throwing machine called a trebuchet. This adapted video segment explores how understanding energy transfer informs their design.

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Engineering Biofuels

In this video segment adapted from KQED's QUEST, find out how synthetic biologists use the techniques of metabolic engineering and directed evolution to make more effective biofuels.

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Ethanol Biofuel

In this video segment adapted from NOVA, learn about one scientist's idea for using biotechnology to make ethanol a more efficient alternative to gasoline.

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Eve: Extreme Ultraviolet Variability Experiment

In this NASA video, scientists describe how the Extreme Ultraviolet Variability Experiment will sample and track the Sun's ultraviolet irradiance, providing a detailed time sequence of extreme ultraviolet output -- data that can provide advance warning for potentially disruptive energy bursts.

Everyday Radiation

How much radiation are we exposed to every day? Find out in this video segment adapted from FRONTLINE.

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