Hewitt-Drew-it! 101. Magnetism

From bar magnets to electric motors.

 

Air Pressure Can Crush with Physics Girl and Walter Lewin

Can crushed by atmospheric pressure.

ScienceCasts: Evidence for Supernovas Near Earth

A NASA sounding rocket has confirmed that the solar system is inside an ancient supernova remnant. Life on Earth survived despite the nearby blasts.

 

Why are Stars Star-Shaped?

Stars are spherical...so why do we draw them with points?

Because of diffraction...

 

Demise of the Kilogram - Sixty Symbols

The days of a "fixed" kilogram seem to be numbered, with moves afoot to set our SI unites based on fundamental constants.

 

NASA | Late Summer M5 Solar Flare

On Aug. 24, 2014, the sun emitted a mid-level solar flare, peaking at 8:16 a.m. EDT. NASA's Solar Dynamics Observatory and STEREO captured images of the flare, which erupted on the left side of the sun. Solar flares are powerful bursts of radiation. Harmful radiation from a flare cannot pass through Earth's atmosphere to physically affect humans on the ground, however -- when intense enough -- they can disturb the atmosphere in the layer where GPS and communications signals travel.

To see how this event may affect Earth, please visit NOAA's Space Weather Prediction Center at http://spaceweather.gov, the U.S. government's official source for space weather forecasts, alerts, watches and warnings. This flare is classified as an M5 flare. M-class flares are ten times less powerful than the most intense flares, called X-class flares.

 

What do plastic bags have in common with metal?

In less than 100 seconds, Adrian Sutton explains why metals and plastic bags deform in different but related ways. Visit physicsworld.com for more videos, webinars and podcasts.

 

Tiny objects levitated by sound

Philip Bassindale, a researcher at the University of Bristol, demonstrates acoustic levitation by creating a “pearl necklace” of polystyrene balls in a standing wave of ultrasound. This video was recorded in connection with a Physics World podcast about the nature and applications of ultrasound, which you can listen to here.

 

How Far Can Legolas See?

Vision is limited by diffraction.

 

How to Find an Exoplanet

These planets are too far away for direct observation.

 

What can Schrödinger's cat teach us about quantum mechanics? - Josh Samani

The classical physics that we encounter in our everyday, macroscopic world is very different from the quantum physics that governs systems on a much smaller scale (like atoms). One great example of quantum physics’ weirdness can be shown in the Schrödinger's cat thought experiment. Josh Samani walks us through this experiment in quantum entanglement.

 Lesson by Josh Samani, animation by Dan Pinto.

 

How Long Can You Balance a Pencil?

Equilibrium.

 

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.

 

ScienceCasts: Sizing up an Exoplanet

Astronomers are not only discovering planets around distant suns, they are also starting to measure those worlds with astonishing precision. The diameter of a super-Earth named Kepler 93B is now known to within an accuracy of 148 miles.

 

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.

 

What Is The Speed of Dark?

Shadows moving faster than light?

 

How Magnets Produce Electricity 1954 US Navy Electromagnetism Prime

How a magnetic field effects a single atom, a group of atoms and a wire in a closed circuit with a meter.

 US Navy training film MN-8016b

 

The Origins of Mass

The Higgs boson was discovered in July of 2012 and is generally understood to be the origin of mass. While those statements are true, they are incomplete. It turns out that the Higgs boson is responsible for only about 2% of the mass of ordinary matter. In this dramatic new video, Fermilab’s Dr. Don Lincoln tells us the rest of the story.