An ice-skater pushes heself away from a wall. She slides on the ice for a distance before stopping. A) has the ice-skater done work when she pushed herself? B) friction is a force. Does friction di work on the ice-skater? Give reasons for you answer
1. An ice-skater pushes heself away from a wall. She slides on the ice for a distance before stopping. A) has the ice-skater done work when she pushed herself? B) friction is a force. Does friction di work on the ice-skater? Give reasons for you answer
jawab
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I agree with CuriousOne that the example is more confusing than helpful, but this is the way I would explain it.
Suppose you take a spring, place it on the ground then compress it. If you now suddenly let go of the spring it will rebound and bounce upwards off the ground:
Spring
The spring clearly has work done on it because its kinetic energy increases and that increase must have come from somewhere. However the ground can't have done any work on the spring because the ground hasn't moved. It should be obvious that the potential energy in the compressed spring has been converted into kinetic energy of the uncompressed spring - in effect the spring has done work on itself. This is what your book means by:
transfers of energy from one type to another inside the object
i.e. potential energy of the compressed spring has been converted into kinetic energy of the uncompressed spring.
In the case of the skater the skater's arms correspond to the spring and the rail corresponds to the ground. The skater's arm isn't a spring, of course, because it's chemical energy not potential energy being converted to kinetic energy by the skater's muscles. Nevertheless the same principle applies.
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Oct 17 '14 at 9:29
John Rennie
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Oct 17 '14 at 14:16
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I think this is a good example, and should be studied and understood carefully. But I don't know where the book goes after making it. Whether or not it is poorly stated depends on the surrounding context.
It focuses attention on two things:
1.) the skater is a deformable body. The center of mass is not fixed in the body.
2.) work is defined as a force times the displacement of the point of application.
(And, arguably a third aspect: the skater carries a store of chemical energy. But this fact is aside the point being made.)
In this case, the point of application does not move. There is no external work from that force. Both of these points are important to understand and remember. Typically, up to this point in a course, problems are implicitly formulated in terms of a point-particle model of an object. No internal structure. When deformable bodies are considered, certain things that work for point-particles no longer work. Additional analysis is needed.
Note that there is internal work being done. Chemical reactions contract muscle fibers. The fibers apply forces to tendons. Now there is a force and a displacement of the application of the force.
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Oct 17 '14 at 12:43
garyp
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So, with your point 2), you mean to say that when a car crashes into a tree, the tree doesn't do any work on the car because the point of application of its force is fixed? –
gatsu
Dec 17 '15 at 6:41
Absolutely correct. –
garyp
Sep 25 '16 at 2:13
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An initially ice-skater pushes away from a railing and then slides over the ice. Her kinetic energy increases because of an external force F⃗ on her from the rail . However, that force does not transfer energy from the rail to her. Thus, the force does no work on her.
This is simply confused: This example is nothing but an elastic collision between the girl and the rail. The example given by John is appropriate but I do not agree with him that the arms behave differently from a spring. Of course the ultimate source of energy is chemical, but the girl as a system behaves exactly like a steel spring or a football hitting the rail.
enter image description here
If the skater (m = 30 Kg) had a spring and was travelling at v = 4 m/s she would have KE = 240 J and would bounce back at (roughly) the same speed. If she stretches her arms and pushes at the rail (like a spring) she can acquire the same speed of 4 m/s producing net work of 240 J. Because of human muscle inefficiency she'll have to burn 4-5 times that amount of calories $\approx 1080 J$
The body is compressed against the rail like an elastic ball, then it stretches back (in a ball the whole body, in a skater the arms, in a swimmer in a pool or in a high-jumper the legs) giving acceleration to the whole body. I
2. Pada diagram tersebut, langkah-langkah untukmenampilkan teks kategori "banyak siswa"seperti teks pada diagram tersebut adalah ....a. klik layout → axis titles - primaryvertical axis titles → left titlesb. klik layout → axis titles → primaryvertical axis titles → left axis titlesc. klik layout → axis titles → primaryvertical axis titles → rotated titlesd. klik layout → axis titles → primaryvertical axis titles → vertical titles
Jawaban:
A. klik Layout → Axis Titles → Primary Vertical Axis Titles → Left Titles
3. Pada gambar diagram tersebut, langkah-langkah untuk menampilkan teks kategori "banyak siswa" seperti teks pada diagram tersebut adalah....a. klik layout --》axis titles --》primary vertical axis titles --》 left titlesb. klik layout --》axis titles --》primary vertical axis title --》left axis titlec. klik layout --》axis titles --》primary vertical axis titles --》rotated titlesd. klik layout --》axis titles --》primary vertical axis titles --》vertical titles
Jawab:
A. klik Layout → Axis Titles → Primary Vertical Axis Titles → Left Titles
4. A skater moves with 15 m/s in a circle of radius 30 m . The ice exert a central force of 450 N. What is the mass of the skater. (GAFSA)
Jawaban:
BANYAK BANGET MASALAH AKU BUNUH DIRI AJA AKU UDAH GK KUAT NAMA AKU SEPTIAN HAKIM MINTA MAAF JIKA ADA SALAH
5. 2. what is the purpose of the text a. to describe ice b. to tell the readers about ice c. to show how to make ice d. to inform the readers about ice
ini soal procedure y? jawabannya : c. show how to make ice.
6. The ice age is about friendship rubah ke 5tense dasar
5 tense dasar? setau sy yang tense dasar hny 3
simple present tense
the ice age is about friendship
simple past
the ice age was about friendship
simple future
the ice age will be about friendship
7. Jabarkan perbedaan antara vertical axis dengan horizontal axis
Jawaban:
Jawaban
Pendahuluan
Sebelum membahas mengenai perbedaan antara vertikal axis dengan horizontal axis, mari kita bahas terlebih dahulu apa itu vertikal axis dan horizontal axis. Kedua istilah tersebut dapat ditemui pada saat kita membuat chart atau membuat grafik baik menggunakan aplikasi microsoft office seperti pada microsoft word, microsoft excel atau aplikasi lainnya.
Pembahasan
Perbedaan diantara keduanya secara umum dapat dilihat pada letaknya, untuk vertical axis merupakan gari tegak ke atas, sedangkan horizontal axis merupakan garis mendatar pada grafik. Vertical axis biasanya digunakan untuk menampilkan suatu jumlah sedangkan horisontal axis biasanya digunakan untuk menampilkan range waktu.
Kesimpulan
Demikian pembahasan mengenai perbedaan antara vertikal axis dan horizontal axis, keduanya merupakan salah satu komponen pendukung yang ada pada suatu grafik. Keduanya memiliki fungsi agar data yang ditampilkan pada grafik mudah untuk dibaca. Untuk mempelajari materi lainnya mengenai cara membuat chart atau grafik serta materi lainnya dapat dibaca pada link berikut
Pelajari lebih lanjut
1. Perintah yang digunakan untuk membuat grafik pada excel brainly.co.id/tugas/2849191
2. Cara membuat grafik pada microsoft word brainly.co.id/tugas/8405880
3. Jenis grafik yang ada pada microsoft excel brainly.co.id/tugas/2504097
Detil Jawaban
Kelas : 7 SMP
Mapel : TI
Bab : Cara membuat grafik pada microsoft office
Kata Kunci: Perbedaan vertical axis dan horizontal axis
8. Dika eats an ice creamit is .....ice creamthe ice cream is....
Jawaban:
1. an vanilla
2. delicious
Penjelasan:
maaf kalo salah
9. An ice crystal is the nuclei on which a hailstone is built
Jawaban:
Crystal ice is used to cool drinks
10. Apa arti dari there is a child buy an ice cream
Jawaban: disana ada anak anak yang sedang membeli es krim
Penjelasan:
11. an ice crystal is the nuclei on which a hailstone is built
3rrrrtysdcrfvygvvgv ghththtvvfcrvt
12. when water is frozen , it becomes .....a. iceb. icesc. the iced. an ice
sepertinya jawabannya b.ices
.is becomes the ice ...
13. Dua pemain sepatu es (ice skater),laki laki bermassa 100kg
Jawaban:
but uh poinhdehhejrhr
14. primary vertical Axis title difungsikan untuk menuliskan keterangan grafik secara
bagian dari grafik
Selain jenis grafik, Anda perlu memahami cara membaca grafik. Grafik mengandung beberapa unsur atau bagian yang berbeda, yang dapat membantu Anda menginterpretasikan data.
Berikut adalah bagian-bagian yang berbeda dari grafik.
Vertical Axis: Sumbu vertikal, juga dikenal sebagai sumbu y, adalah bagian vertikal dari grafik. Di sini, sumbu vertikal mengukur nilai dari kolom. Pada contoh kita, nilai yang menguasai adalah total penjualan masing-masing genre.
Judul Bagan: Judul harus menggambarkan dengan jelas apa yang digambarkan pada grafik.
Horizontal Axis: Sumbu horizontal (juga dikenal sebagai sumbu x) adalah bagian horizontal dari grafik. Di sini, sumbu horizontal Mengidentifikasi kategori pada grafik. Dalam contoh ini, setiap genre ditempatkan dalam kelompok sendiri.
Seri Data: Serial data terdiri dari titik-titik data yang terkait dalam grafik. Dalam contoh ini, seperti yang kita lihat dalam legenda, kolom kuning mewakili penjualan bersih pada bulan Februari.
Legenda: Legenda Mengidentifikasi setiap data serial yang mewakili masing-masing grafik warna. Dalam contoh ini, legenda Mengidentifikasikan bulan yang berbeda pada grafik.
15. spinning is jawabannya adalah maksudnya
Jawaban:
berputar adalah
jawabnnya
jadikan jawaban ini yang terbaik
Jawaban:
Berputar
#Maap klo slh :)
16. Demain buys an ice cream. it is like a cone. it is ... ice cream
Jawaban:
It is an ice cream
Penjelasan:
Jawaban:
Demain buys an ice cream, it is like a cone. it is an ice cream.
17. apa yang dimaksud vertical axis?
Jawaban :
Vertical axis adalah garis tegak lurus keatas
18. A: "What is the shape of an ice cream?" B: "It is ..... A : "Can you draw an ice cream?" B: "Yes, ....
Jawaban:1. it is a circle
2. Yes,i can
Penjelasan:sorry if not correct
19. Jelaskan yang kalian ketahui tentang vertical Axis
vertical axis merupakan garis tegak ke atas
Jawaban:
vertical axis merupakan garis tegak ke atas
Penjelasan:
Semoga membantu
Maaf kalo kurang pemahamannya
20. apa yang dimaksud vertical axis??
Jawaban:
vertical axis merupakan garis tegak ke atas sedangkan horizontal axis merupakan garis mendatar pada grafik
Jawaban:
vertical Axis merupakan garis yang tegak ke atas
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