Definition 20.5.1. Electric field.
The electric field is a vector field that influences the force that a charged object experiences.
Section 20.5 Electric Field
Subsubsection Key Ideas
Charged particles exist throughout the world and interact with each other through electric fields. Electric fields exist everywhere in space and are generated by charges. The motion of charged objects through space is governed by any pre-existing electric fields.
Definition 20.5.2. Electric force.
The electric force on a point-like object (test charge) is the product of the object’s charge and the electric field at the location of the object:
\begin{equation*}
\vec{F}^E = q_{\text{test}} \vec{E}
\end{equation*}
Note 20.5.3. Gravity and Electricity.
Like the gravitational force, the electric force is a non-contact force, as opposed to a contact force. The electric and gravitational fields are responsible for the force between charges and masses, respectively. Much of what you will do in exploring electric fields has a direct analogue with gravitational fields.
Subsubsection Activities
Activity 20.5.1. Fields in Science.
An electric field is a field, which means it has a potentially different value everywhere in space. Identify one other quantity you are familiar with that could be described as a field. It can be from physics or from another science, or from your everyday experience. Explain why you believe the quantity you chose is a field.
Activity 20.5.2. Sensemaking: Units.
What are the units of the electric field?
Activity 20.5.3. How Flowers Talk to Bees.
Watch
this video describing how flowers and bees communicate. Can you think of other ways in which plants and animals might rely on, use or be affected by electric fields?
References References
[1]
"How flowers talk to bees 😯" YouTube, uploaded by ByteBrilliance, 17 January 2024, https://www.youtube.com/watch?v=ee381dCP6JM&ab_channel=ByteBrilliance
