Physicist Felix Bloch developed a non-destructive technique for precisely observing and measuring the magnetic properties of nuclear particles. He called his technique "nuclear induction," but nuclear magnetic resonance (NMR) soon became...

Willem Einthoven invented a string galvanometer that lead to the electrocardiogram, which measures heart activity. For his discovery, Einthoven was awarded the Nobel Prize in Physiology or Medicine in 1924.

Karl Jansky discovered extraterrestrial radio waves while investigating possible sources of interference in shortwave radio communications across the Atlantic for Bell Laboratories, and is often known as the father of radio astronomy....

Charles-Augustin de Coulomb invented a device, dubbed the torsion balance, that allowed him to measure very small charges and experimentally estimate the force of attraction or repulsion between two charged bodies. The data he obtained...

A teacher lesson plan is provided here. This page describes two activities in which the effect of multiple resistors on the current and overall resistance of both series and parallel circuits are investigated. Complete activity...

This site briefly defines Joule's Law. A formula is provided and links to related terms.

Explore how a capacitor works! Change the size of the plates and add a dielectric to see how it affects capacitance. Change the voltage and see charges built up on the plates. Shows the electric field in the capacitor. Measure voltage...

Through eight lessons, students are introduced to many facets of dams, including their basic components, the common types (all designed to resist strong forces), their primary benefits (electricity generation, water supply, flood...

Students use a watt meter to measure energy input into a hot plate or hot pot used to heat water. The theoretical amount of energy required to raise the water by the measure temperature change is calculated and compared to the electrical...

Students learn about the anatomy of the ear and how the ears work as a sound sensor. Ear anatomy parts and structures are explained in detail, as well as how sound is transmitted mechanically and then electrically through them to the...

On a windy day it is hard to keep your hat on. The power of the wind can even be strong enough to power large wind turbines to make electricity. In this experiment, find out how you can make your own instrument to measure the speed and...

Students complete three different activities to evaluate the energy consumption in a household and explore potential ways to reduce that consumption. The focus is on conservation and energy efficient electrical devices and appliances.The...

Counting alpha particles was tedious and time-consuming work, until Hans Geiger came up with a device that did the job automatically.

In this activity, students explore how an electrochemical cell works. They use a Voltage Sensor to measure the electrical energy produced when the distance between the electrodes is varied. They also determine the factors that affect the...

Inside your brain, you have over 80 billion neurons - tiny brain cells, all working together to make you the person you are.Neurons talk to each other by sending electrical messages. Each message creates a tiny magnetic field. If enough...

In this activity, students develop an understanding of how engineers use wind to generate electricity. They will build a model anemometer to better understand and measure wind speed.

This lab is designed to have students investigate the different changes that could be made to an air filled capacitor and the results that occur because of these changes. Students can vary the gap between the plates, the size of the...

The Earth, the moon, the stars and just about everything in between has a magnetic field, and scientists use magnetometers when they need to know the strength of those fields.

Practice reading an analog current meter.

See how Ohm's Law can tell us that the voltage across resistors will depend on that current value I and each R-value.

Use the tutorial to find the total resistance for resistors in a series circuit.

Use resistance formulas to determine the total resistances of the series and parallel parts. Then, use Ohm's Law to calculate the voltage drops across and currents through each part.

Use the series and parallel resistance formulas to determine the total resistances of the parts. Then, use Ohm's Law to calculate the voltage drops across each part.

See how this application of Ohm's Law leads to a formula for the total of parallel resistances.