3. • Explain the concept of electric charge and
its interaction.
• Explain that an object can be electrically
charged by being rubbed
• Calculate the interactional force between
electric charges by using Coulombs law.
• Explain the concept of electric field
4. Klik STATIC ELECTRIC
Listrik Tidak Mengalir
Klik Plastic ruler
Litle Paper tear
Klik
Why is plastic ruler that is rubbed on hair
can pull little papers?
To get answer question upon us need to understand
Klik about atom.
6. Klik 2. Atom Helium ( He ) 3. Atom Litium ( Li )
Klik
Klik How many proton on Helium
upon?
How many elektron on Helium
Klik upon?
Klik How many proton on Lithium atom
What is Helium atom gets
Klik electricity? upon?
Klik How many electron on Lithium
Klik Why is Helium atom neutral? atom upon?
Klik What is Lithium atom gets
Klik Conclusion electricity?
if which atom was said by
neutral? Klik Why is Lithium atom neutral?
7. Getting electricity on object by rubs
Klik Klik
Klik
Klik
Plastic that rubbed by woolen clothes, therefore
plastic wills be get negative electricity, since
woolen’s electron migrant to plasctic.
8. Getting electricity on object by rubs
Klik Klik
Klik
Klik
glass that rubbed by silk therefore glass wills be
get positive electricity, since glass electron
migrant goes to silk.
9. Klik
Interaction among electricity
Klik
repeled
Klik like charges repel each other
10. Klik Interaction among electricity
Klik
attrated
Klik unlike charges attract each other.
12. • The force between two charges is equal to
Coulomb’s constant, times the product of
the two charges, divided by the square of
the distance between them.
F = coulomb force( N )
q1 q 2
F k 2 q = charge ( C )
r r
k
= distance ( m )
= coulomb constanta
Satuan SI Cgs
F N dyne
Q C Stc
r m cm
K Nm2/C2 dyne cm2/ Stc2
Nilai 9.109Nm2/C2 1 dyne cm2/ Stc2
13. Klik
Example
• Two charges Q1 and Q2, have 3µC dan –
Klik
2 µC are separated by a distance 10 cm if
Coulombs Constanta is 9.109 N m2/C2
What total force are them?
Klik
Q .Q Catatan
F k 1 22
R Ubah satuan – satuan
6 6
3.10 C.2.10 C besaran yang ada
F 9.109 Nm 2 / C 2
(0,01m) 2 kedalan satuan SI
9 23.10 6 C.2.10 6 C
2
F 9.10 Nm / C μC = 10 –6 C
(0,0001m 2 )
cm =10 –2 m
9 23.10 6 C.2.10 6 C
2
F 9.10 Nm / C
10 4 m 2
F = 54 N
14. Klik
Electric field
Klik The electric field is the space around an
electrical charge which is still influenced by the
Klik
object’s electric charge.
Klik E
q
Q
E
q
Q
The more far the location of the test object from charged objects Q then
Klik the force gets smaller influence so strong electric field is getting smaller
15. Klik
Coulomb force’s Lines
• Electric field figured by Coulomb force’s
lines.
Klik Klik
Direction of electric lines of Direction of electric lines of
force charge positif, leaving a force charge negative, toward
charge the charge
16. Klik The pattern on the electric lines of
force
Klik Klik
Klik Klik
17. Klik
Strong electric fields
Benda bemuatan listrik Q didekatkan benda uji bermuatan q berjarak r
Klik Besar kuat medan listrik di titik benda uji adalah gaya listrik yang
ditimbulkan benda bermuatan di bagi muatan uji
Q q
Klik E
r
Klik
Klik
F Qq E = electric field ( N/C )
E E k 2 Q = Source Charge ( C )
q r q q = test charge ( C )
r = distance ( m )
F = Coulomb Force ( N )
Q
E k 2
r
18. Klik
Electrostatic Induction
Klik
Netral
Klik
What happens to the charge neutral object ,when
Klik
approached by a positively charged object?
Klik
Conclusion:
Elctrostatic induction is the phenomenon where
electric charge separate in neutral object when a
object closed by elictric charge.
19. Klik Getting negative electricity on
object with induction
Klik
Neutral
Klik
Bumi
Klik
Negatif charge
Klik
Neutral objects when induced by positively
charged objects will become negatively charged
20. Klik Getting a positive electric charge on
an object by induction
Klik
Neutral
Klik
Bumi
Positif charge
Klik Neutral objects when induced by negatively
charged objects will become positively charged
Conclusion type objects induced charge opposite to the type of
Klik
content objects that induce
21. Klik Getting a negative electric charge by touching
objects.
Klik Neutral
Klik
Negatif
charge
Neutral objects when touched by a
Klik
negatively charged object will become
negatively charged
Klik How do we explain when a neutral object when the
object is positively charged touched the neutral object
become positively charged?
22. Klik
Elektoscope
• The instrument used to determine the electrical
charge on the object.
Elektroscope heaad
conduktor
Elektroscope leaf
Glass wall
23. Klik
Karya Kreatif
Tujuan : Membuat Elektroskop Sederhana
Alat & bahan :
1. Botol bekas kecil
2. Alluminium foil (bekas bungkus rokok )
3. Kawat tembaga 15 cm
4. Amplas
5. Gabus
6. penggaris plastik
Langkah – langkah
1.
Klik Ambil Alluminium fiol bekas bungkus rokok dan
pisahkan kertas yang menempel pada Alluminium
dengan cara membakarnya hingga Alluminium bersih
dari kertas yang menempel.
2.
Klik Potong Alluminium foil dengan ukuran 0.5 cm x 4 cm
24. Klik Amplas kedua ujung kawat tembaga dan tekuk salah satu ujung kawat
3.
tembaga hingga berbentuk seperti gambar.
4. Letakkan potongan Alluminium foil pada ujung kawat tembaga yang telah
Klik ditekuk lalu lipat Alluminium foil tersebut seperti gambar.
5. Masukkan kawat tembaga yang telah diberi Alluminium foil ke dalam botol
Klik dan tutup botol dengan gabus seperti gambar.
6. Remas Alluminium foil dan tancapkan pada ujung tembaga yang diluar botol
Klik Gosokkan penggaris plastik pada rambut dan dekatkan pada kepala
7.
elektroskop yang telah kamu buat amati apa yang terjadi dengan daun
elektrokop ?
3 cm
Di amplas
3 cm
1 2 3 4 5
Klik Klik Klik Klik
25. Klik
Electroscope working principles:
at neutral electroscope leaves covered
at Charged electroscope leaves covered
26. Klik
Electricity on electroscope with induction
Klik Klik
Klik
Netral Electroscope head Klik
Klik Electroscope head is Klik Electroscope
closeed by touched out hand negatively
positively charged therefore electron from charged
object, electron earth go to lectroscope become
from leaf moves to and counteracts since accepts
head and electroscope leaf, electron from
electroscope leaf therefore electroscope earth
opens leaf close
Jenis muatan benda terinduksi berlawanan dengan jenis muatan benda yang menginduksi
Klik
Bagaimana kalau yang didekatkan pada kepala elektoskop benda bermuatan negatif
Jelaskan !
27. Klik
Kilat
Because the house
has a huge barrier
when the electrons
pass through a large
Klik number of houses will
be damaged, which
means that the house
was struck by
lightning.
28. Prinsip Kerja Penangkal Petir 1 Ketika rumah
Klik terinduksi oleh awan
yang bermuatan
sehinga atap rumah
menjadi bermuatan
positif maka muatan –
Klik muatan negatif awan
mengalir dari awan
kebumi melewati
Penangkal petir penamgkal petir,
Klik karena penangkal petir
terbuat dari bahan
konduktor yang baik
maka ketika dilewati
muatan listrik negatif
dari awan tidak
menyebabkan
kerusakan.
29. Prinsip Kerja Penangkal Petir 2 Ketika rumah
Klik terinduksi oleh awan
yang bermuatan
sehinga atap rumah
Klik
dan penangkal petir
menjadi bermuatan
positif karena
Klik penangkal petir terbuat
dari bahan konduktor
Penangkal petir yang ujungnya runcing
maka udara disekitar
penangkal petir akan
terionisasi ion negatif
akan ketarik penangkal
petir dan dialirkan
kebumi sedangkan ion
positif akan ketarik
awan dan menetralkan
awan .
30. Generator Van de Graff
Klik
• Mesin pembangkit listrik Prisip kerja
Klikstatis yang sangat besar
Gesekan antara silinder
Politen logam dengan sabuk karet
menghasilkan muatan listrik
Klik Klik negatif pada sabuk karet dan
Bola Konduktor muatan negatif dialirkan ke
bola konduktor.
Bola konduktor akan
bermuatan negatif yang
sangat besar.
Sabuk Gesekan antara politen
karet dengan sabuk karet
menyebabkan sabuk karet
nemjadi bermuatan positif
karena sabuk karet yang
bermuatan positif
dihubungkan dengan bumi
logam maka elektron dari bumi
menetralkan muatan positif
pada sabuk karet.
31. TAGIHAN SOAL 1
Klik
Pemahaman Konsep
1. Lengkapi nama – nama partikel penyusun atom pada model atom di bawah
Model atom
…………………….
…………………….
…………………….
…………………….
2. Atom natrium ( Na ) dan atom klor ( Cℓ ) yang semula netral kemudian
karena sesuatu hal satu buah elektron terluar dari atom natrium pindah ke
atom klor menyebabkan atom natrium kehilangan ………… dan menjadi
bermuatan ……………, sedagkan atom klor menerima …………… dan
menjadi bermuatan ………………
3. Kaca yang digosok dengan kain sutra menjadi bermuatan listrik dan
ditetapkan jenis muatannya adalah ……………………..Jelaskan secara
listrik statis kaca dapat ermuatan listrik tersebut !
4. Gaya apa yang muncul ketika plastic bermuatan yang digantung pada statif
didekati dengan kaca bermuatan yang kita pegang tangan …………………
5. Faktor apa yang mempengaruhi besar gaya listrik antara muatan …………
6. Gambar arah medan listrik pada dua muatan positif yang berdekatan ?
7. Apa yang dimaksud dengan Induksi listrik
32. • Kinerja Ilmiah
1. Lengkapi gambar peristiwa induksi di bawah dengan menambahkan
muatan yang terdapat pada kepala dan daun elektroskopnya serta
jelaskan terjadinya dengan teori listrik statis ?
a. b.
2. Jelaskan mengapa balon yang digosok – gosok dengan kain dapat
menempel pada kaca
3. Jelaskan prinsip kerja alat penangkal petir sesuai konsep listrik
static.
4. Dua buah muatan listrik yang masing-masing 4 C dan 3 C
menimbulkan gaya listrik sebesar 8 N, jika jarak antara kedua
muatan diperbesar menjadi 2 kali semula berapakah besar gaya
listrik yang muncul sekarang ?
5. Dua bola kecil yang bermuatan listrik sama
dan sejenis digantung dengan tali seperti gambar.
Jika besar gaya tolak yang muncul antara
kedua muatan 0,1 N dan k = 9.109 N m2/C2
berapakah besar muatan masing-masing ?
3 cm
33. 1. Glass rubbed on silk will be positively charged because ....
a. Electron move from the glass to silk
b. Proton move from the glass to silk
c. Electron move from silk to glass
d. Proton move from silk to glass
2. The attractive or repulsive force betwwen two electric
charge is ....
a. Inversely proportional to their charges
b. Directly proportional to the square of their charges
c. Inversely proportional to the square of intercharge
distance
d. Directly proportional to the square of intercharge
distance
34. 3. Two electric charge, q1 and q2, at a certain
distance (r), produce repulsive force F. If q1
is changed five times larger and the distance
of two charge changed three times larger, the
repulsive force becomes ....
a.5/3 F
b.5/6 F
c.5/9 F
d.9/5 F
35. 4. Two object have electric charge of 2 x
10-5 C and 5 x 10-6 C is separated at a
distance of 3 cm. If the constant k = 9
x 109 N m2/C2, the force between two
object is equal ....
a.1 N
b.10 N
c.100 N
d.1000 N
36. 5. Look at the table below.
An object with electric Interaction
charge
X Y Repel each other
X Z Attract each other
Y Z ...........
The interaction between Y and Z is ....
a. Repel each other
b. Attract each other
c. No effect at all
d. neutral
37. 6. The interaction between two charges is F.
If the distance of two charges becomes
twice as much, their electric force is ....
a. 0.20 F
b. 0.25 F
c. 0.40 F
d. 0.50 F
38. 7. The region around electric charge that is
still influenced by elektric force is called ....
a. Electric field
b. Coulomb’s force
c. Electric potential
d. Magnetic field
•
39. 8. Electric field strength is ....
a. Force per unit area
b. Force per unit charge
c. Work per unit area
d. Work per unit charge
40. 9. Study the statement below.
1. Disimilar electric charge repel each other
2. An object will be negatively charged if the number of
electron is more than the number of protons
3. Disimilar electric charge attract each other
4. An object will be positively charged if the number of
electron is more than the number of protons
The correct statements ....
a. 1 and 2
b. 1 and 3
c. 2 and 3
d. 2 and 4
•
41. 10. Consider the statements below.
1. Field lines never cross each other
2. Field lines always go inward approaching a
negative charge
3. Field lines always go outward approaching a
negative charge
4. Field lines always go outward approaching a
positive charge
5. The correct statements of electric field is shown by
numbers ....
a. 1, 2, and 3
b. 1, 3, and 4
c. 2, 3, and 4
d. 1, 2, and 4
