The Physics of Hot Air Balloons

How to Escape Quicksand

You probably won’t get stuck in quicksand. But if you do, you can use physics to get yourself out.

 

Why Raindrops Are Mathematically Impossible

Rain shouldn't happen, according to basic physics.

 

How Do Airplanes Fly?

How do airplanes fly?

 

Using Lasers to Create Super-hydrophobic Materials

Scientists at the University of Rochester have used lasers to transform metals into extremely water repellent, or super-hydrophobic, materials without the need for temporary coatings.

 

How a Crookes radiometer works

A Crookes radiometer is driven by a thermal gas effect, and not "light pressure" as often thought. Ben Krasnow demonstrates the radiometer in a vacuum chamber and explain its optimal running pressure.

 

Air Pressure Can Crush with Physics Girl and Walter Lewin

Can crushed by atmospheric pressure.

Why do ice cubes crack in drinks?

Dropping ice cubes in water (and liquid nitrogen) produce interesting results. Differential expansion.

 

Magnetic Hair

MIT engineers have fabricated a new elastic material coated with microscopic, hairlike structures that tilt in response to a magnetic field. (Learn more about these structures: http://bit.ly/1y2E8SX) Depending on the field's orientation, the microhairs can tilt to form a path through which fluid can flow; the material can even direct water upward, against gravity.

 

How do tornadoes form? - James Spann

Tornadoes are the most violent storms on Earth, with wind velocities that can exceed 200 miles per hour. How do these terrifying cyclones form? Meteorologist James Spann sheds light on the lifespan of tornadoes as they go from supercell thunderstorms to terrible twisters before eventually dissolving back into thin air.

 Lesson by James Spann, animation by Província Studio.

 

Why is ketchup so hard to pour? - George Zaidan

Ever go to pour ketchup on your fries...and nothing comes out? Or the opposite happens, and your plate is suddenly swimming in a sea of red? George Zaidan describes the physics behind this frustrating phenomenon, explaining how ketchup and other non-Newtonian fluids can suddenly transition from solid to liquid and back again.

Lesson by George Zaidan, animation by TOGETHER.

 

A Baffling Balloon Behavior - Smarter Every Day 113

Helium balloon in an accelerating car.

 

Hewitt-Drew-it! PHYSICS 93. Water and Electron Circuits

The similarities and differences between electric and hydraulic circuits.

 

NASA | Jewel Box Sun

This video of the sun based on data from NASA's Solar Dynamics Observatory, or SDO, shows the wide range of wavelengths -- invisible to the naked eye -- that the telescope can view. SDO converts the wavelengths into an image humans can see, and the light is colorized into a rainbow of colors.

As the colors sweep around the sun in the movie, viewers should note how different the same area of the sun appears. This happens because each wavelength of light represents solar material at specific temperatures. Different wavelengths convey information about different components of the sun's surface and atmosphere, so scientists use them to paint a full picture of our constantly changing and varying star.

Yellow light of 5800 Angstroms, for example, generally emanates from material of about 10,000 degrees F (5700 degrees C), which represents the surface of the sun. Extreme ultraviolet light of 94 Angstroms, which is typically colorized in green in SDO images, comes from atoms that are about 11 million degrees F (6,300,000 degrees C) and is a good wavelength for looking at solar flares, which can reach such high temperatures. By examining pictures of the sun in a variety of wavelengths -- as is done not only by SDO, but also by NASA's Interface Region Imaging Spectrograph, NASA's Solar Terrestrial Relations Observatory and the European Space Agency/NASA Solar and Heliospheric Observatory -- scientists can track how particles and heat move through the sun's atmosphere.

 The 2.9 minute movie was created by NASA's Scientific Visualization Studio or SVS at NASA's Goddard Space Flight Center in Greenbelt, Maryland, and is available at the SVS website: http://svs.gsfc.nasa.gov/goto?11385

 

How to float a ping pong ball on air - The Coandă Effect

Widely explained using the Bernoulli principle, this phenomenon is actually dominated by the Coanda effect.

 

ScienceCasts: Starting Fire in Water

Astronauts on the ISS are experimenting with a form of water that has a strange property: it can help start fire. This fundamental physics investigation could have down-to-Earth benefits such as clean-burning municipal waste disposal and improved saltwater purification.

 

Hewitt-Drew-it! 81. Thermodynamics

The three laws of thermodynamics are cited and explained.

 

Hewitt-Drew-it! 79. Energy of Phase Changes

The roles of heat of fusion, and vaporization, in changes in phase.

Hewitt-Drew-it! 75. Heat Transfer

Conduction, convection, and radiation.

 

Hewitt-Drew-it! 80. More on Phase Changes

Phase changes are explained and expressed in equation form.