Electricity

In the late 1700s, Italian scientist Luigi Galvani stumbled across one of the most important discoveries of all time. He found that frog legs would contract when some of the muscles and nerves were connected – even when the frog was dead! Galvani attributed this phenomenon to the idea that animal and human brains produce [...]

The link between electricity and magnetism finds its legendary roots back to Hans Christian Orsted when he supposedly found that electric current affected his compasses during a student lecture. That piece of scientific history may be one of exaggerated legend, but the marriage of electricity with magnetism has been widely known for over a century, later to be given a full mathematical explanation by Lord Kelvin and James Clerk Maxwell. The concept of electron movement causing the production of an ensuing magnetic field is a fundamental model used in describing electromagnets, generators, transformers and electric motors.

In 1820, Danish physicist/chemist Hans Christian Ørsted noticed that when current from his Voltaic pile was switched on and off, a compass needle placed near the wire deflected from true magnetic north. Within a few months of careful study, he deduced that a magnetic field circles a current-bearing wire.

Using high voltage equipment in the classroom can be exciting and educational for students, but most students AND teachers do not realize the real-life applications of such devices in their everyday lives. Although high voltage components are used in many of today’s electronic gadgets, being able to demonstrate the principles of this electrical phenomenon can be confusing for students and may present a safety issue for the teacher if not properly used.

Looking for a Hands-On Activity to Excite your Students about Learning Electricity?In this issue of CoolStuff we have just the thing! A series of hands-on electricity activities that students can use to to explore key electricity concepts. No matter what level students you teach, elementary, middle school, or high school; we have something for everyone. Real life electricity investigations where your student's see, hear, and feel actual results in electronic configurations.

This simple Homopolar Motor shows how moving charges (an electric current) experience a force when they move through a magnetic field. When the wire is in place, current flows from the battery’s positive terminal, through the wire, radially through the magnet, and into the battery’s negative terminal.

One of the first science toys I ever owned was a water rocket. Essentially a plastic container with fins, the rocket is prepared for flight by partially filling it with water and pressurized air. When released, the rocket’s contents exit a small hole at the base of the rocket in one direction, pushing the rocket ahead with amazing speed in the opposite direction. A case of action-reaction, pure and simple.

You might assume that most of your students are capable of lighting a light bulb given a battery, a bulb, and a single strand of wire. In actuality, when faced with this challenge, some students may succeed at the task immediately while others may never be able to make the bulb light without assistance.

The electrical force is so pervasive that it is difficult to name many aspects of the physical world not affected by it. At the most fundamental level, the attractive electrical force between electrons and protons holds atoms together. On a bit larger scale, electrical interactions between atoms are responsible for the formation of molecules. On a much grander scale, a rapid discharge of atmospheric electricity manifests itself as a flash of lightning. All these phenomena are governed by the same basic principles.

Hands on activities including counting calories in the classroom with potato chips, show potential energy and the conservation of energy with a pendulum, similarities with generators and electric motors, Watts Up meter measurements, and sugar linked to strength.