Simple Conservation of Mass Activity

October 5, 2010

Lee Walkerby: Lee Walker

When we are doing a Partnership for Learning.com Science Adventure on phases of matter we like having this conservation of mass experience in the bag of tricks. It can be done in minutes and is extremely reliable. All you need is the simplest (and least expensive) OHAUS classroom balance from Educational Innovations, the Ice Melting Block set from Educational Innovations, a pair of wire cutters and some paper clips, (just in case you need to whip up some mass bits of less than a gram) and a nicely formed ice cube. We like to use the aluminum blocks and O-rings from two of the Ice Melting Block sets just to simplify the balancing and have found that having more than one set of the blocks is good for the original activity anyway.

Here we go……. Read the rest of this entry »

Leave a Comment » | Chemistry, College level, Elementary level, experiments, High School level, Middle School level, Physics | Tagged: , , , | Permalink
Posted by Tami O'Connor

Mixing Light Colors with the Three Port Light Source

September 24, 2010

Marty SagendorfBy: Martin Sagendorf

We see hundreds of colors, but the colors we think we see are often not what we’re actually seeing – i.e. many of these colors are combinations of other colors.  ‘Light’s Story’ is fascinating and full of surprises.  It begins with knowing that radiating and re-radiating substances emit light.  The light colors emitted are functions of a number of factors: the substance, or the incident light, or the temperature of an incandescent source.

All the textbooks explain ‘additive’ and ‘subtractive’ colors.  Explanations are fine, but actual experience makes both an immediate impression and a very lasting learning experience.  For example, here’s how only RED, GREEN, and BLUE light colors combine to produce two new unexpected colors.

Mixing Light - Educational Innovations

But we’re getting ahead of ourselves… let’s start with something we’re really familiar with: pigment colors.  We all know that mixing different paint (pigment) colors will produce new colors.  For example, when we mix red and green pigments we ‘see’ brown. And, as everyone knows, mixing a wide range of pigment colors will produce the ‘color’ we see as black.  But, odd things happen when we mix two light colors.  We don’t get the same color that we obtained when we mixed pigments.

When we mix red and green light colors we don’t ‘see’ brown: we see yellow!  How can this be?  Then… even though it does appear even more counter-intuitive, the mixing of all light colors produces the color we ‘see’ as white (but has NO color? – white… or does it?). Read the rest of this entry »

1 Comment | Biology, College level, experiments, High School level, Middle School level, Physics | Tagged: , , , , | Permalink
Posted by Tami O'Connor

Density of Gasses

August 13, 2010

Tami O'Connor, Educational Innovationsby:  Tami O’Connor

Why do some objects float while others sink?  Archimedes discovered that an object is buoyed upward with a force equal to the weight of the fluid displaced.  An object will float in a fluid whenever its weight is less than the weight of the fluid displaced; otherwise it will sink…  So what does this mean in English??? An easier way to think about it is that an object that is less dense than the fluid it is in will rise to the top of the more dense fluid.

In demonstrations of liquids of varying densities, the liquid with the greatest density will sink to the bottom of the container while the less dense liquid will remain on the top.  There are wonderful demonstrations you can conduct with your class using immiscible liquids (liquids that do not mix) of different densities, and there are a number of high interest experiments your students can conduct using liquids of different densities.  If you find this topic interesting, please visit the blog we wrote on the W-Tube.

Demystifying the Poly Density Bottle-Educational Innovations Blog

Gasses also have varying densities, but in the elementary and middle school classrooms, students don’t often have the same opportunity to work with gasses as they would liquids, or more often, liquids and solids. Read the rest of this entry »

Leave a Comment » | Chemistry, density, Elementary level, experiments, Middle School level | Tagged: , , , , , , | Permalink
Posted by Tami O'Connor

Bring Some Magic Into Your Classroom!

July 10, 2010

Ted Beyer, Educational Innovationsby Ted Beyer

One of my favorite authors, Arthur C. Clark, once said, “Any sufficiently advanced technology is indistinguishable from magic.” This has been quoted, misquoted and reused for years.  Of course, it’s perfectly true, and magicians have been using science as part of their acts for centuries. Things that we take for granted today were once bleeding edge technology. I remember in high school reading that sometime ‘soon’ (this was more than 30 years ago) there would be TVs that would be so thin that they would hang on the wall like pictures – impossible! A generation before, the concept of television itself was astonishing, and a generation before that, moving pictures of any kind were magical.

As I started to think about this, I suddenly realized that there are many products that we sell here at Educational Innovations that are used – currently – by magicians as ‘tricks’ in their act. Let’s take a look…. Read the rest of this entry »

Leave a Comment » | Chemistry, College level, Elementary level, experiments, High School level, Middle School level, Physics | Tagged: , , , , , , , , , , , , | Permalink
Posted by Tami O'Connor

Concentrating Sunlight: It’s Easy!

July 9, 2010

Marty Sagendorfby: Martin Sagendorf

On a Bright Day:

A great deal of energy falls on the Earth’s surface – roughly 1 kW per square meter.  This is about 0.6 Watt per square inch.  This doesn’t sound like much energy, but suppose we collect and concentrate 63 square inches of this sunlight?  These 63 square inches would collect about 38 Watts of energy.  This doesn’t sound like much, but…

Suppose We Could Then:

Concentrate these 38 Watts into an area of only 1/8 of a square inch?  This is exactly what we can do with an inexpensive plastic Fresnel lens.  We’ll focus the sunlight into an area 3/8” in diameter – this is the equivalent of 300 Watts per square inch!  With this energy level, we can easily ignite a piece of wood, boil some water, and even melt a penny.

A Suitable Device:

Is described in the book, Physics Demonstration Apparatus and in the blog The Sun’s Energy.

Now we’re going to describe how to build a much simpler version that works just as well – one that uses a very inexpensive Fresnel lens and is very easy to construct. Read the rest of this entry »

7 Comments | College level, energy, experiments, High School level, Physics | Tagged: , , , , , | Permalink
Posted by Tami O'Connor

« Previous Entries
Next Entries »