The purpose of our concept map is to map out the various concepts taught under
electrostatics, taking into account the order in which we want to teach the concept
in electrostatics , and the grades we want to teach them in. This map is a tool for
both teacher and student: we as the teachers would consolidate this map to ensure
we are covering all the main concepts to be taught, and to determine whether there
were any misconceptions the students could have or any concepts needing revision.
The learners will utilise this map for the same purposes, but to also use it to make a
detailed summary of the sections. They can do this by filling in details around the
concept to create a comprehensive map of electrostatics, to act as a tool for
revision. This map will be introduced at the beginning of teaching the section and
learners will have to make a copy of it. As we teach each concept, we will ask
learners to fill in the main details around each concept. Therefore at the end of each
lesson, learners will get a chance to reflect on the concepts they were taught and
assess whether they need certain points to be revised by the teacher (this can be
done at the end of the lesson, if time permits or in the beginning of the next lesson
before moving on). Learners will see which concepts they are going to focus on in
their level, as well as have an idea of where they are progressing towards. This map
will be developed over the 3 years they are learning electrostatics.
Electrostatics is the study of stationary electric charge. The concept of charge comes
from the basic building block for all matter, the atom. Atoms consist of protons,
neutrons and electrons. Protons are positively charged, neutrons are neutrally charged
while electrons are negatively charged. The charge of an object or substance is based
on the number of electrons and protons in the atom. It is important to note that the
number of protons doesn’t change in an atom, while the number of electrons can vary.
Neutrally charged objects contain equal number of protons and electrons. Positively
charged objects have less electrons than the constant number of protons and
negatively charged objects have more electrons than the constant number of protons.
These are the factors that determine the charge of an object or substance.
Charge conservation is the principle that the total electric charge in an isolated system
doesn’t change. An isolated system indicates that in this system, there is a particular
amount of charge and no exterior charge can affect this system.
A stationary charge is a charge that is not in motion. Its S.I unit is the coulomb, a
coulomb is the amount of charge from 1 ampere of current flowing per second, 1
coulomb is equal to the charge of 6.241 x 1018 protons. The stationary charge is
measured by charge quantization, this means that when we say something has a
given charge, we mean that that is how many times the charge of a single electron it
has. Using this we can figure out whether a charge is negative or positive and from
there we can observe how the charges interact with each other, such as like charges
repelling each other and opposite charges are attracted to each other, from this we
can measure the magnitude of the force from these interactions between the charges.
Grade 11
In Grade 10, the learners would have learnt about the force between charges. In
grade 11 they will learn exactly how to determine this force and about a basic law of
electrostatics. The force is determine by Coulomb’s Law: 𝐹 =
𝑘 𝑄1 𝑄2
𝑟2
K is the proportional constant which equals 9.0 × 109 𝑁𝑚2 𝐶 −2 in free space. Force (F)
is measure in Newton’s (N). This sections is mostly calculations using the equation, so
learners have to finalize themselves with the equation and substituting into the
equation. In the following chapter learner will learner that these charges have an
electric field around them and how the electric field has electric field line. They will
calculate the electric field using: =
𝐹
𝑞
=𝑘
𝑄
𝑟2
, where E is measured in Newton per
Coulomb (N/C). The learners will go deep into the section as the chapter progress,
looking at how the density of electric lines determine the strength of the field, by
drawing more field lines around the greater charge.