Viola Putri

1. Simbiosis mutualisme dapat ditunjukkan dengan
kehidupan dari ...

A. tali putri dan tanaman beluntas
B. benalu pohon inangnya
C. lalat dan bunga Raflesia
D. semut dan kutu buah



2. Manusia mampu mengubah ekosistem karena ...

A.etiap perubahan ekosistem oleh manusia selalu
menguntungkan
B.setiap perubahan ekosistem oleh manusia selalu
merugikan
C.setiap perubahan ekosistem haras diperhitungkan
masak-masak
D.manusia tidak usah mengubah ekosistem.


3. Tujuan PPA ialah ...

A. melestarikan hewan, tumbuhan dan alamnya
B. melestarikan bangunan-bangunan kuno
C. melestarikan monumen-monumen bersejarah
D. melestarikan fosil-fosil di musium


4. Yang mempunyai umbi batang ialah ...

A. umbi jalar
B. umbi talas
C. umbi kayu
D. umbi bawang


5.Hewan ternak yang bermanfaat bagi manusia dan hidup
di air tawar adalah ...

A. kerang hijau
B. remis
C. cumi-cumi
D. tiram


6. Meja belajar yang dipakai siswa-siswa kelas 1 SLTP
ternyata terlalu rendah. Bila hal itu dibiarkan terus akan
mempengaruhi sikap duduk siswa yang salah dan dapat
mengakibatkan

A. kelainan pada tulang belakang
B. tulang belakang menjadi lebih pendek
C. tulang belakang menjadi lebih panjang
D. sumsum tulang belakang akan menyempit


7. Tepung yang belum berubah di mulut akan mengalami
perubahan dalam ...

A. usus oleh ptialin
B. pankreas
C. usus oleh amilase
D. pankreas oleh ptialin


8.Seorang anak yang muntaber dianjurkan untuk minum
air yang diberi garam dan gula yang banyak. Hal ini
disebabkan karena ...

A.garam dan gula membantu membunuh bakteri-
bakteri penyebab muntaber
B.untuk mengganti air, garam dan gula yang keluar
dari tubuh
C.aram dan gula akan melambatkan pengeluaran
kotoran
D.pengeluaran kotoran akan berhenti karena gula dan
garam tidak menghasilkan sisa pencernaan

9. Gelombang elektromagnetik antara 10–5 – 10–4 meter
(infra merah) hanya dapat ditangkap dengan baik oleh
alat indra ...
A.mata
B.telinga
C.kulit
D.hidung


10. Sehelai daun telah disimpan dalam ruang gelap selama
3 hari, dimasukkan dalam alkohol yang mendidih
sehingga klorofilnya larut. Jika iodium diteteskan pada
daun itu, yang sekarang tidak mengandung klorofil,
warna daun berubah menjadi ...

A.cokelat
B.ungu
C.biru hitam
D.kembali hijau lagi

15. “Choose one that has a high water efficiency rating when purchasing a washing machine.”
(sentence 1)
The underlined word means ......
a. Selecting
b. Operating
c. Buying
d. Using

16. To reduce the use of water when laundering we can do the following, except .....
a. Delay washing until we have full load of clothes
b. Choose washing machine which uses less detergent.
c. Wash whenever we have dirty clothes.
d. Choose a washing machine with high water efficiency rating

17. When laundering, we must choose the detergent which is .....
a. Friendly
b. Phosphorus
c. Bio-degradable
d. Limited

18. From the text above we know that a front loading washing machine is ..... than a top loading
machine.
a. Cheaper
b. More energy
c. More expensive
d. More efficient

19. To be efficient in using water, we must ….
a. Use a top loading washing machine
b. Purchase a washing machine
c. Only use phosphorus detergent
d. Wait until we have full load to wash the clothes.


STEVE’S CROC EXPRESS
Southern Queensland is home of the Crocodile Hunter and Australia Zoo, made famous by global
documentaries and antics of Steve and Terry Irwin.
On the way to Australia Zoo you’ll view the majestic Glasshouse Mountains bordered by Pine
Forests and Pineapple Plantation.
Today you will have time to really experience the best of Australia Zoo, set over 70 acres of natural
bush land. Spend 6 hours taking in the many shows, talks, and demonstrations, including crocodile
feeding, tigers, birds of prey show and snake handling. Throughout the day you’ll have the
opportunity to get up real close with a few of the locals! Don’t forget to give the awesome elephants
an apple or two or talk to the cute wombat called Megs.
Includes: Entry to Australia Zoo, all shows and attractions, commentary and touring.

20. The text above tells us about …..
a. The crocodile Hunter
b. The tourist’s attraction in Southern Queensland
c. Australia Zoo
d. Global documentaries

21. The tourist can see …. on their way to the zoo.
a. Glasshouse Mountain
b. Pine Forest
c. Pineapple Plantation
d. Crocodile Hunter

22. The visitors of the Australia Zoo usually gives the elephants …..
a. Peanuts
b. Potatoes
c. Apples
d. Pineapples

23. In the Australia Zoo, visitors ….
a. Can only see the animals from a distance
b. Can also feed the animals there
c. Can talk to the crocodile
d. Can give demonstration and talk

24. The ticket for a child is …..
a. The same as adults
b. More expensive than adults
c. Higher than adults
d. Half-price of adults

25. Salsa : Look at the building!
    Havis : Wow, ……………………
    Salsa : Yeah. It’s the biggest building in this town
a. How big is the building
b. What a big building
c. How nice building
d. What pretty the building is

The Sahara Desert is the largest desert in the world. It is bigger than the four next largest deserts put
together. It is as vast as the whole of the United States of America including most of Alaska and nearly
as big as the whole of Europe.
The Sahara desert was once green with trees ad plants. Giraffes, elephants, and rhinos wandered
across it. We know this because they are shown in rock paintings found in south-east Algeria, drawn
thousands of years ago.
Even as recently as the 1820s a French explorer heard lions roaring in the forest where now there is
only desert. The world’s deserts are growing bigger. The Sahara is growing by 1,5 million hectares
every year. That is an area three quarter the size of Wales every year, or four football fields every
minute.
26. The communicative purpose of the text above is …..
a. To share an amusing incidents with the readers
b. To inform the readers the beauty of the desert
c. To describe the Sahara Desert
d. To persuade people to go to Sahara Desert

27. The following are TRUE about Sahara Desert EXCEPT …..
a. It is the largest desert in the world
b. It is larger than United States
c. It becomes larger and larger
d. It had many animals thousands years ago.

28. “We know this because they are shown in rock paintings. “(paragraph 2). The word “they”in
the sentence above refers to …..
a. The Sahara Desert
b. The plants
c. The paintings
d. The animals

29. Ardi : I didn’t see your car yesterday. Where was it?
Linda : it ….. by my brother
a. Borrowed
b. Is borrowed
c. Was borrowed
d. Has borrowed

30. Nanik : What does your father do every afternoon?
Indah : He ….. in the living room
a. Read newspapers
b. Reads magazines
c. Is reading newspapers
d. Was reading magazines

Snakes are reptiles. They belong to the same group as lizards (the scaled group, Squamata) but for a
sub-group of their own (Serpentes)
Snakes have two legs but a long time ago they had claws to help them slither along. Snakes are not
slimy. They are covered in scales which are just bumps on the skin. Their skin is hard and glossy to
reduce friction as the snake slither along the ground.
Most snakes live in the country. Some types of snakes live in trees, some live in water, but most
usually consists of frogs, lizards, and mice and other snakes. The Anaconda can eat small crocodile and
even wild boards.
Many snakes protect themselves with their fangs. Boa Constrictors can give you a bear hug which is
so powerful it can crush every single bone in your body. Some snakes are protected by scaring their
enemies away like The Cobra. The flying snakes glided away from danger. Their ribs spread apart and
the skin stretches out. Its technique is just like sugar gliders.
Text source: Derewianka, 1990.
31. What is the main idea of the text?
a. Snakes are reptile
b. Snakes have two legs
c. Most snakes live in the country
d. Many snakes protect themselves with their fangs.
32. Paragraph ….. describes about the physical description of snakes.
a. One
b. Two
c. Three
d. Four

33. The following statements are true, except …….
a. All snakes live in the country
b. Snakes can be found mostly in the ground.
c. Cobras protect themselves by scarring their enemies away.
d. A snake does not only eat frogs and lizards but also other snakes

34. “A snake’s diet usually consists of frogs, lizards, and mice and other snakes.” (paragraph 2).
The word diet has the same meaning as …..
a. Enemy
b. Predator
c. Prey
d. Friend

35. X : Look, the snake is eating our rabbit. Let’s kill it !
Y : No, …. The snake belongs to endangered species. It’s protected by government. Let it go.
a. I believe it
b. It’s a good idea
c. It’s not a good idea
d. I am not sure about that

One day, a young wanderer got lost in a wood. Suddenly he saw a light from an old hut. He knocked on the door, and an old woman opened it. She was crying. She said that the devil had stolen her magic
candle. The candle could grant anything she asked. The wanderer asked her where the devil lived. “In a
castle not far from here,” said the old woman.
The wanderer went to the castle. There he found the devil, but he was old and weak. Therefore when
the wanderer grabbed the magic candle from the devil’s table and ran away, he couldn’t chase him.
But the wanderer was not a kind man. He didn’t return the candle to the old woman, but kept it for
himself. He lit the candle and made a wish, “I want to go far away from here.” Suddenly, genies
appeared and took him to a beautiful palace. There was a party in the palace. The wanderer wanted to
make some money. So he lit the candle again and wished for some jewelry. He sold them to the guests
and was soon making a lot of money. Then the Princes came to buy the jewelry, but there was nothing
left. The wanderer felt in love with her and asked her to marry him. The kind Princess said yes, and
they got married the next day. In his happiness, the wanderer told the Princes about his adventure and
the magic candle. Hearing that, the Princes got very angry. At night she lit the candle and wished that
the wanderer disappear.
In the morning the wanderer awoke and found him self back in his ugly house in the village.

36. What does the text above tell about? It tells about .....
a. An old hut
b. An old woman
c. A magic candle
d. A kind young wonderer

37. The wanderer found .... when he got the castle.
a. An old woman
b. A kind princes
c. A genie
d. And old devil

38. How often did the wanderer light the candle for his wishes?
a. Once
b. Twice
c. Three times
d. Four times
39. What's the moral value of the story about?
a. To be rich is not important
b. To be kind is not important
c. It is very important for everyone to be rich
d. It is very important for everyone to be kind

40.     X : Why are you crying old woman, what's the matter with you?
Y : I've lost my magic candle, young wanderer.
Yesterday, an old devil came to my hut and ........ it from me.
X : Okay, please don't cry anymore. Let me find him and take the candle back to you.
a. Steal
b. Stole
c. Stolen
d. Steals

Do you like making snack by yourself? What kind of snack do you like? Well, .... do you like
making jelly snack? If you do, you may choose one kind of it, Nutrijell.
How do you make it? Now, follow these instructions:
Prepare a sachet of Nutrijell powder, a pan, three and half glasses of water, five spoonfuls of
sugar depending on your taste., and some jelly moulds.
First, mix well jelly powder with five spoonfuls of sugar. After that, pour the mixture into seven
hundred ml of water, stir till dissolved and boll. Then, pour the solution into the jelly moulds. Wait a
few minutes until cool. The jelly snack is ready.

41. Why did the writer wrote the passage?
a. to entertain the readers
b. To show how to make Nutrijell
c. To describe what the Nutrijell is
d. To inform the readers about what happened

42. To make Nutrijell we need the materials such as .....
a. Nutrijell powder, water, sugar
b. Nutrijell powder, water, sugar, sachet
c. Nutrijell powder, water, sugar, sachet, pan
d. Nutrijell powder, water, sugar, sachet, pan, moulds

43. Which one belongs to the third stage of making Nutrijell?
a. Prepare a sachet of Nutrijell powder
b. Pour the solution into the jelly moulds
c. Mix well jelly powder with five spoonful of sugar
d. Pour the mixture into seven hundred ml of water

44. The word ..... in the text above means “stir”
a. Pour
b. Mix
c. Boil
d. Prepare

45.     Astri : First, mix well jelly powder with fivd spoonful of sugar, then pour the mixture into
seven hundred ml of water.
Alya : We have to stir the mixture till dissolved, ....... we?
Astri : That's right. Then, boil the mixture, pour into the jelly moulds, wait a few minutes until
cool, and the jelly snack is ready.
a. Do
b. Don't
c. Did
d. Didn't

46. Last Sunday I (46) ....... up very late. I looked out of the window. It was dark (47) ....... very
silent outside. “What a day!” I thought. “It was raining again”. Just then, the telephone rang. It
was my aunt Lucy. She asked (48) ....... if I was fine.

a. Get
b. Got
c. Gotten
d. Getting

47. a. But
b. Or
c. And
d. If

48. a. Mine
b. My
c. Me
d. I

Listrik Statis Kelas IX SMP

Category: Fisika SMP

Written by fisikastudycenter

Fisikastudycenter.com, membahas Listrik Statis, Materi Fisika SMP Kelas IX (9). Teori singkat, inti atom, interaksi bahan-bahan, dan memuati elektroskop disertai contoh soal hitungan sederhana dan pembahasan.






Inti atom
Partikel-partikel penyusun suatu atom:
Elektron → bermuatan negatif
Proton→ bermuatan positif
Neutron→ tidak bermuatan
Inti atom terdiri dari proton dan neutron, sementara elektron bergerak mengelilingi inti atom dalam lintasan tertentu.

Interaksi Muatan-Muatan
Muatan yang sejenis akan saling tolak (plus dengan plus, minus dengan minus)
Muatan yang berlawanan jenis akan saling tarik(plus dengan minus)

Besar gaya tarik atau gaya tolak tersebut bisa ditemukan dengan rumus berikut:


Dimana
F = gaya tarik menarik atau gaya tolak menolak dalam satuan newton (N)
q₁ = besar muatan pertama dalam satuan coulomb (C)
q₂ = besar muatan kedua dalam satuan coulomb (C)
k = konstanta gaya coulomb yang nilainya 9 x 10⁹ dalam satuan yang standar
Catatan

• 1μC = 10⁻⁶ C = 0,000001 C (sepersejuta)
• Jika menjumpai muatan negatif, tidak perlu diikutkan tanda  minusnya dalam perhitungan.

Muatan Bahan-Bahan
Sebaiknya dihafal saja, muatan-muatan dari interaksi berbagai kombinasi (gosok-menggosok) bahan berikut:

Bahan-bahan	Hasil	Proses
Kaca - Kain Sutera	Kaca (+), Sutera (−)	Elektron dari kaca berpindah ke kain sutera
Mistar plastik - Kain wool	Mistar plastik (−), Kain wool (+)	Elektron dari kain wool berpindah ke mistar plastik
Sisir - Rambut Manusia	Sisir (−), Rambut Manusia (+)	Elektron dari rambut manusia berpindah ke sisir
Penggaris/mistar plastik - Rambut manusia	Penggaris (−), Rambut Manusia (+)	Elektron dari rambut manusia berpindah ke penggaris
Balon - Kain Wool	Balon (−), Kain Wool (+)	Elektron dari kain wool berpindah ke balon
Ebonit - Kain Wool	Ebonit (−), Kain Wool (+)	Elektron dari kain wool berpindah ke ebonit

Kesimpulan dari tabel diatas (TERBATAS UNTUK BAHAN-BAHAN TERSEBUT saja) :
-Bahan yang digosok , (yang sebelah kiri) semuanya menjadi negatif , kecuali kaca.
Elektron dari kaca berpindah ke kain sutera bisa juga dibahasakan, kain sutera mendapatkan tambahan elektron dari kaca, elektron dari kain wool berpindah ke mistar plastik bisa juga di katakan, mistar plastik mendapatkan tambahan elektron dari kain wool dan seterusnya.
Elektroskop
Berikut ilustrasi saat sebuah elektroskop netral di dekati oleh benda bermuatan negatif.

                                         

Ilustrasi saat sebuah elektroskop masih netral, intinya adalah jumlah muatan positif sama dengan jumlah muatan negatif, baik di kepala (atas) maupun di daun kaki (bawah).

Sebuah benda bermuatan negatif kemudian didekatkan ke elektroskop.

               

Muatan negatif dari benda akan tolak menolak dengan muatan negatif dari kepala elektroskop, sehingga muatan negatif di kepala elektroskop kemudian menjauh jalan-jalan ke bawah /kaki.

Akibatnya, daun kaki yang tadinya netral, seimbang jumlah plus minusnya, sekarang menjadi menjadi lebih banyak muatan negatifnya, akhirnya kaki elektroskop akan terbuka akibat gaya tolak menolak muatan negatif di kaki kiri dan kanan elektroskop.

           
Bagamana jika elektroskop kondisi awalnya tidak netral, tapi sudah bermuatan positif atau negatif terlebih dahulu?
Kita coba terapkan pada soal berikut, dari soal Ebtanas IPA tahun 1990 (dah lahir beluum,..)

• Gambar manakah yang benar untuk sebuah benda bermuatan listrik negatif didekatkan pada elektroskop bermuatan listrik positif?

           
Ntar kita jawab jg di sini, yang jelas antara B atau C krn bagian kepala musti positif,  skrg diskusikan dulu ya,..elektroskop positif itu yang seperti apa dan bagaimana sebuah elektroskop bisa menjadi bermuatan positif.

Contoh-Contoh Soal Hitungan di Listrik Statis 9 SMP
1) Dua buah muatan masing-masing q₁ = 6 μC dan q₂ = 12 μC terpisah sejauh 30 cm. Tentukan besar gaya yang terjadi antara dua buah muatan tersebut, gunakan tetapan k = 9 x 10⁹ dalam satuan standar!

Pembahasan
Data dari soal:
q₁ = 6μC = 6 x 10⁻⁶ C
q₂ = 12μC = 12 x 10⁻⁶ C
r = 30 cm = 0,3 m = 3 x 10⁻¹ meter
F = ....?
Dari rumus gaya coulomb didapatkan



2) Dua buah muatan listrik memiliki besar yang sama yaitu 6 μC. Jika gaya coulomb yang terjadi antara dua muatan tadi adalah  1,6 C      1,6 N, tentukan jarak pisah kedua muatan tersebut!

Pembahasan
Data :
q₁ = 6μC = 6 x 10⁻⁶ C
q₂ = 6μC = 6 x 10⁻⁶ C
F = 1,6 C   1,6 N
r =....?

Gunakan rumus yang sama dari soal nomor 1


Salah rupanya,..kita cuba sekali lagi,..

Jarak kedua muatan dalam centimeter adalah 45 cm.  (Thanks to sahs & raqib atas koreksinya,...)
3) Dua buah benda bermuatan listrik tidak sejenis, tarik-menarik dengan gaya sebesar F. Jika jarak kedua muatan didekatkan menjadi 1/3 kali semula, maka gaya tarik-menarik antara kedua muatan menjadi...F

Pembahasan
Dari rumus gaya coulomb di atas terlihat bahwa besarnya gaya berbanding terbalik dengan kuadrat jarak kedua muatan. Jadi (1/3)² adalah 1/9 kemudian dibalik menjadi 9/1 atau 9 saja. Jadi jawabannya adalah menjadi 9 F

4) Dua buah benda bermuatan listrik tidak sejenis, tarik-menarik dengan gaya sebesar F. Jika jarak kedua muatan dijauhkan menjadi 4 kali semula, maka gaya tarik-menarik antara kedua muatan menjadi...F

Pembahasan
Dari rumus gaya coulomb di atas terlihat bahwa besarnya gaya berbanding terbalik dengan kuadrat jarak kedua muatan. Jadi (4)² adalah 16 atau dalam pecahan 16/1, kemudian dibalik menjadi 1/16. Jadi jawabannya adalah menjadi 1/16 F

5) Titik A dan titik B mempunyai beda potensial listrik sebesar 12 volt. Tentukan energi yang diperlukan untuk membawa muatan listrik 6μ Coulomb dari satu titik A ke titik B!

Pembahasan
Berikut rumus untuk menentukan jumlah energi yang diperlukan untuk membawa atau memindahkan muatan antara dua buah titik:

W = Q × ΔV

dimana:
W = energi atau usaha  yang diperlukan dalam satuan joule (J)
Q = besar muatan dalam satuan Coulomb (C)
Δ V = beda potensial atau selisih potensial antara dua titik dalam satuan volt (V)

Sehingga:
W = Q × ΔV
W = 6μC × 12 volt = 72 μJ

6) Dua buah partikel bermuatan listrik didekatkan pada jarak tertentu hingga timbul gaya sebesar F. Jika besar muatan listrik partikel pertama dijadikan 1/2 kali muatan semula dan besar muatan partikel kedua dijadikan 8 kali semula maka gaya yang timbul menjadi....
A. 0,5 F
B. 4 F
C. 8,5 F
D. 16 F

Pembahasan
Dari rumus gaya coulomb di atas, terlihat besarnya gaya sebanding dengan besar perkalian kedua muatan. Sehingga tinggal dikalikan saja 1/2 × 8 = 4 . Jadi hasilnya adalah B. 4 F

Nilai (x)	Frekuensi (f)
3	5
4	8
5	7
6	12
7	3

Nilai (x)	Frekuensi (f)
5	2
6	3
7	8
8	4