Bill Nye on Energy

This episode covers different forms of energy, including potential and kinetic, which you'll see again in 8th grade.


Electrical energy

Study Jams: Electricity

Study Jams: Electricity

Bill Nye: Electricity

Bill Nye: Electricity


Magnetic energy

Warning: This video is NOT designed to give a middle school-level understanding.  It's really complex!

Bill Nye on magnets

Iron filings (tiny bits of iron) can be used to see what a magnetic field looks like.  Even though the magnetic energy is invisible, it causes the iron filings to line up in patterns.  Click on an image to enlarge.

 

Watch these iron filings move as a magnet is moved around underneath them.

"Same poles repel and opposites attract!"


Electromagnets

 

Bonus: Electrical generation

Just like we've seen that ELECTRICITY can create MAGNETS (electromagnets), the same thing can be done in reverse.  In fact, the electricity that is powering your computer as you look at this website was produced in a power plant using giant spinning magnets.  How does that work?  Check out these videos:


Sound energy

Sound moves in  compressional waves.   This animation shows how compressional waves travel.  Watch the red dots.  Notice that these particles  vibrate  (bounce back and forth), but none of them actually travel all the way across the screen.  It's the energy itself (the  movement  or  change ) that travels from the left side all the way to the right side.  The wave is really formed by the interaction between energy and matter, as the sound energy makes the molecules vibrate.

Sound moves in compressional waves.  This animation shows how compressional waves travel.  Watch the red dots.  Notice that these particles vibrate (bounce back and forth), but none of them actually travel all the way across the screen.  It's the energy itself (the movement or change) that travels from the left side all the way to the right side.  The wave is really formed by the interaction between energy and matter, as the sound energy makes the molecules vibrate.

 
This Slinky also shows how compressional waves travel.  Imagine pushing and pulling one end back and forth.  The rings compress for a moment, then return to their starting positions, but the vibration spreads down the length of the Slinky.

This Slinky also shows how compressional waves travel.  Imagine pushing and pulling one end back and forth.  The rings compress for a moment, then return to their starting positions, but the vibration spreads down the length of the Slinky.

 

Rather than just moving down a line, sound waves actually spread out in all directions.  These three images give you a better idea of what sound waves would look like if you could see them moving through the air.  Even better, check out the videos below to see sound in action!

Frequency is the number of waves that pass by per second.  Pitch is how high or low the sound is.  The faster something is vibrating, the higher the frequency of the sound waves will be, and the higher the pitch will be when you hear it.

Frequency is the number of waves that pass by per second.  Pitch is how high or low the sound is.  The faster something is vibrating, the higher the frequency of the sound waves will be, and the higher the pitch will be when you hear it.

The frequency of a wave can be represented on a graph like this.

The frequency of a wave can be represented on a graph like this.

Neat experiments with sound energy:


Light energy

Study Jams: Light

Study Jams: Light

Study Jams: Reflection, Refraction, Absorption

Study Jams: Reflection, Refraction, Absorption


Energy 101 Videos

This Youtube playlist includes 20 short videos produced by the US Department of Energy.  Learn about how we get power from heat buried inside the earth, from wind and sun, even from biofuels made from microscopic living things!  Find out what a fuel cell is, and how an electric car works!


Simple Machines