Lesson Plan of Static Electricity General Science Grade V
Lesson Plan of Static Electricity
General Science Grade V
Students’ Learning Outcomes
·
Explain the production of
static electrical charges in some common materials.
·
Explain the phenomenon of
lightening.
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Information for Teachers
·
All materials are made of atoms
which contain protons, electrons and neutrons.
·
Protons have positive
charges, electrons have negative charges and neutrons have no charge.
·
The protons and electrons are
equal in numbers in an atom. Therefore net charge on an atom is zero.
·
The electrons are loosely
attached to the atom.
·
When two objects are rubbed
together, some electrons from one object move onto the other.
·
Thus, the number of electrons
on one object becomes greater than the number of protons in it, so negative
charge appears on it.
·
The number of electrons left
on the other object becomes less than the number of protons on it, so positive
charge appears on it.
·
There is attraction between
two oppositely charged objects.
·
There is repulsion between
two similarly charged objects.
·
When oppositely charged
clouds come close to each other, they collide with each other due to great
attraction and thus a big spark is produced. It is called as lightning.
Material / Resources
Balloons, thread, stand, woolen cloth, plastic
comb, metallic key, textbook
Worm up Activity
·
Ask the students; have they ever observed that
when a plastic comb is rubbed through hair and brought near small paper bits,
it begins attracting these paper bits.
(Expected response: Yes)
·
Ask: have
they observed that a woolen trouser often sticks to the hair on their legs?
(Expected response: Yes)
·
Now tell the students that when a plastic comb
is rubbed through hair, it becomes charged and this starts attracting hair and
paper bits. Similarly, the trouser on rubbing with body hair also becomes
charged and starts attracting body(hair) and sticks to legs. Tell the students
that many such objects acquire charge when rubbed with each other. For example:
---When glass rod is rubbed with silk cloth, it becomes charged.
---When an ebonite rod is rubbed with woolen cloth, it also gets
charged.
Development
Activity 1
·
Divide the class into
suitable groups.
·
Ask a student from each group
to suspend an inflated balloon with the stand by means of a thread.
·
Direct him to bring a piece of
woolen cloth near it. Ask: Does it attract the balloon towards it?
(Expected response: No)
·
Ask the student to rub the
balloon vigorously with a woolen cloth and then remove it away.
·
Direct him to bring the cloth
close to the balloon slowly. Ask the student: Does the cloth attract the
balloon this time?
(Expected response: Yes)
·
Ask the students: Why does
the cloth attract balloon after rubbing?
(Expected response: because the cloth and balloon have acquired
opposite charges)
·
Ask the students to suspend
two inflated balloons with the stands with the help of thread and place them at
some distance from each other.
·
Ask them to bring the
balloons closer by moving the stands.
·
Ask them: Do the balloons
attract or repel each other or nothing happens?
(Expected response: Nothing
happen)
·
Ask them to rub each balloon
with woolen cloth and bring them closer again and observe their movements.
·
Ask them: Do they attract or
repel each other?
(Expected response: They
attract each other because they have opposite charges.)
·
After these activities
explain the cause of attraction or repulsion of balloons.
·
Tell them that when certain
objects are rubbed with each other, they become charged.
·
When two objects are rubbed
some electrons from one object move onto the other. In this way the number of
electrons on one object becomes greater than protons in it and thus it becomes
negatively charged. On the other hand, the number of electrons on the other
object becomes less than protons in it and thus it becomes positively charged.
Activity2
(This activity should be
performed in a dark room)
·
Give each group a plastic
comb, a woolen cloth, an iron nail or key.
·
Ask the students to charge
the comb by rubbing it with the woolen cloth.
·
Ask them to touch the charged
comb gently with a metallic key and observe.
·
Ask the students: What do
they see?
(Expected response: A spark)
·
Explain that when charged
comb is brought closer to the key, opposite charge appears on the near part of
the key. Spark is produced when oppositely charged objects touch each other.
·
Explain that similarly when
oppositely charged clouds come closer to each other, they collide due to great
attraction between them and thus a big spark is produced. It is called
lightning.
Sum up/ Conclusion
·
The charge is the basic
property of matter.
·
The charges are of two types.
One type is called positive and the other negative.
·
On rubbing two objects,
positive charge appears on one object and negative charge on the other object.
·
Opposite charges attract each
other and similar charges repel each other
·
Spark is produced when two
oppositely charged objects touch each other.
Assessment
·
To assess the understanding
of the students ask the following questions:
-----How can an inflated balloon be
charged?
-----why do positive or negative charges
appear on the objects on rubbing?
-----How does lightning occur?
Follow up
·
Ask the students to identify
some objects that can be charged than the ones used in the class activities.
·
Ask them to write down an
activity to charge one of the objects that they have identified.
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