Overview
The high speed of electrical signals results from the fact that the force between charges acts rapidly at a distance. Thus, when a free charge is forced into a wire, the incoming charge pushes other charges ahead due to the repulsive force between like charges. These moving charges move the charges farther down the line. The density of charge in a system cannot easily be increased, so the signal is passed on rapidly. The resulting electrical shock wave moves through the system at nearly the speed of light. To be precise, this fast-moving signal, or shock wave, is a rapidly propagating change in the electrical field. Good conductors have large numbers of free charges. In metals, the free charges are free electrons. The distance that an individual electron can move between collisions with atoms or other electrons is quite small. The electron paths thus appear nearly random, like the motion of atoms in a gas. But there is an electrical field in the conductor that causes the electrons to drift in the opposite direction (opposite to the field, since they are negatively charged). The average velocity of the free charges is known as the drift velocity and is represented in meters per second. Drift velocity is quite small, in the order of 10−4 m/s, since there are so many free charges. Free-electron collisions transfer energy to the atoms of the conductor. The electrical field does work in moving the electrons over a distance, but that work does not increase the kinet…
Embed Tool
Show this article's:
Embed code vs URL
An embed code allows you to place a JoVE video directly inside of your learning or training environment. Most learning management systems such as Canvas, Blackboard, and Moodle require an embed code for JoVE content to stream.
A URL allows you to place a link in programs such as PowerPoint or Microsoft Word which takes a user to a separate page where they can watch a JoVE video.
Most of the time, you will want to use the embed code. However, there are some environments that don’t support embed codes such as Google Classrooms and MS Teams. In those instances, you can use a URL to still provide access to JoVE videos.
What is an Embed Code?
Basically, it’s a snippet of code that you put on your website that displays as a video. An embed code pulls the video from the original source, allowing you to display a video without having to host the file on your website.
How to embed a video
STEP 1: COPY YOUR EMBED CODE
To generate the embed code, simply click the Copy button above. You can customize it by choosing a specific language for the video, or setting exact dimensions for the video player.
STEP 2: PASTE THE EMBED CODE INTO YOUR ENVIRONMENT
Embed codes can be used in most learning management systems (Canvas, Blackboard, Moodle…), organizational websites, and a host of other tools. The specifics of how to add in an embed code will depend on your environment.
Generally, it involves accessing a text editor, entering the HTML mode on the editor, and pasting in the embed code. Get more details on embedding into specific environments here.