Summary of Definición del campo eléctrico | Física | Khan Academy en Español

00:00:00 - 00:15:00

In this video, we learn about electric fields and how they are created by electric charges. We also learn about the powerful effect that electric fields have on objects located in their vicinity. This video is important for physics students because it explains the relationship between electric fields and electric forces.

• 00:00:00 In this video, Khan Academy teacher Luis Salinas explains the concept of electric fields. He explains that when two charges are oppositely charged, they will repel each other. However, if you want to move something that is in the room where you are, you need to touch it. However, the blue charge in this situation seems to be pushing the green charge without even touching it - something that is quite strange. Scientists have been trying to understand this strange phenomenon for centuries, but have not been able to figure out how it works. Michael Faraday and his mathematical understanding of electric fields helped solve this mystery in the 1800s. Since that time, scientists have been aware of the electric field and its relationship to forces, and have been able to use it to predict the trajectories of planets and comets. However, the public is still not entirely familiar with the concept of electric fields, which can lead to misunderstandings about electric forces. People who suffer from electric forces should be aware that electric fields are not forces, but vector representations of those forces. These vectors do not have the same meaning as traditional force vectors, which are drawn as arrows. People who are unfamiliar with electric fields may be confused by this difference and end up believing that electric fields are powerful forces.
• 00:05:00 In this video, Michael Faraday explains how electric fields are created and how two objects that are not in close contact can still exert a force on each other. He calls this phenomenon "field effect." Field effect is what allows an object to know what force to exert on another object in order to keep it in its vicinity. This is what Faraday was trying to explain to physicists when he said "this is what happens...you have a charge with one that creates a field in all space surrounding it including this point where we put this second charge. When it arrives at this point, it will sense the electric field and will exert the same force on this second charge as it does on anything else that is in this region." This field effect is how electricians and physicists keep things local by knowing the space around an object.
• 00:10:00 The field of electricity surrounds everything within a certain radius. We will call this radius "2," as it is created by the two charges. It does not create its own electric field around itself, as other charges do. Rather, it creates an electric field by interacting with other charges. Conceptually, this is how electric fields work. We can understand electric fields without knowing the charge creating it, as long as we know the force exerted on any charge in the field. In this example, I place a small charge (2kg) near a large charge (10kg). I measure the electric field exerted on the small charge, and find that it is 10 Newtons (N) between the two charges. This gives us a field of 5 N around the small charge. The electric field tells us how many charges are in a certain area.
• 00:15:00 In this video, Khan Academy explains the concept of electric fields. We learn that electric fields are created by electric charges and that they have a powerful effect on objects located in their vicinity. This video is important for physics students because it explains the relationship between electric fields and electric forces.