Build the Simplest Electric Motor – submitted by Flinn Scientific Canada

Introduction

Hans Christian Oersted (1777–1851), a Danish physicist, was performing an experiment in 1820 when he noticed that whenever an electric current from a battery was switched on or off, a nearby compass needle was deflected. Through additional experiments, Oersted was able to demonstrate the link between electricity and magnetism. The following year, English scientist Michael Faraday (1791–1867) created a device that produced “electromagnetic rotation.” This device is known as a homopolar motor since the motor requires no commutator to reverse the current.

A motor converts electrical energy to mechanical energy. The simple motor in this activity changes the electrical energy output by the battery to mechanical energy as the copper wire is set into rotational motion. Any current-carrying wire produces an associated magnetic field. The electrons in the wire are subjected to a magnetic field and experience a force—referred to as the Lorentz force—that is perpendicular to both the magnetic field and the direction of movement. At some point along the length of the wire, the electrical current is not parallel to the magnetic field. The resulting Lorentz force is tangential and induces a torque on the copper wire. This torque causes the copper wire to spin.
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How CRISPR lets you edit DNA – TED Talk by Andrea M. Henle

From the smallest single-celled organism to the largest creatures on Earth, every living thing is defined by its genes. With recent advancements, scientists can change an organism’s fundamental features in record time using gene editing tools such as CRISPR. But where did this medical marvel come from and how does it work? Andrea M. Henle examines the science behind this new technology. Continue reading

Introduction to Electrophoresis – submitted by Flinn Scientific Canada

Introduction

Deoxyribonucleic acid (DNA) is the genetic material found inside the nucleus of eukaryotic organisms. The information coded by DNA determines the characteristics of an organism, including its size, shape and other unique features. How can this genetic material be isolated and identified? This activity describes one of the most common techniques used to examine DNA—electrophoresis. Continue reading

Forensics and Biotechnology Safety – submitted by Flinn Scientific Canada

Basic biotechnology lab experiments involving the isolation, digestion and analysis of DNA are an exciting part of the modern biology curriculum. Today’s students are eager to learn about forensic investigations, DNA forensics and other biotechnology applications. This safety note discusses safety issues associated with forensic inquiry and biotechnology experiments. Continue reading

Strawberry DNA – Food Science | Science Experiments | Steve Spangler Science

In this lab, you extract and isolate DNA from strawberries using simple, household ingredients.

You’ve probably learned or heard about DNA, but have you ever seen it? With the Strawberry DNA experiment, you’ll extract, isolate, and observe the DNA of a strawberry in a matter of minutes. It sounds impossible, but thanks to special characteristics of strawberries, it’s actually very possible… and simple. You don’t have to be a geneticist and you don’t need an electron microscope. It’s easy, fun, and all you need are some household materials.

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