Saturday, February 4, 2012

Hukum Kekekalan Energi Mekanik

aplikasi energi mekan
Hukum kekekalan Enegi Mekanik berbunyi Pada sistem yang terisolasi (hanya bekerja gaya berat dan tidak ada gaya luar yang bekerja) selalu berlaku energi mekanik total sistem konstan. Pada posting tentang macam-macam bentuk energi diantaranya adalah energi potensial dan energi kinetik.

Energi total yang dimaksud pada hukum kekekalan energi mekanik adalah jumlah antara energi potensial dengan energi kinetik.

Energi potensial
Energi potensial adalah energi yang dimiliki benda karena kedudukannya. Energi ini tersembunyi pada benda tetapi bila di beri kesempatan energi ini bisa di manfaatkan contoh misalnya energi potensial pada pegas yang ditarik terjadi juga pada pada karet atau busur panah. Contoh yang kedua adalah Energi potensial gravitasi yaitu energi yang dimiliki benda yang disebabkan oleh ketinggian terhadap suatu titik acuan tertentu.
Besar energi potensial gravitasi sebanding dengan massa, percepatan gravitasi serta ketinggian

Ep = m g h

  • m=massa(kg)
  • g=percepatan gravitasi(m/s2)
  • h=ketinggian(m)
Energi Kinetik
Energi kinetik adalah energi yang dimiliki benda karena geraknya misalnya anak panah yang lepas dari busur memiliki kecepatan dan massa tertentu maka anak panah tersebut memiliki energi kinetik yang besarnya berbanding lurus dengan massa serta kecepatan kuadrat.  Dalam persamaan
Ek = ½ mv2
  • Ek= energi kinetik(Joule)
  • m=massa(kg)
  • v=kecepatan(m/s)
Energi Mekanik
Energi mekanik adalah jumlah total dari energipotensial dengan energi kinetik atau
Em= Ep + Ek
Menurut hukum kekekalan energi mekanik bahwa jumlah energi mekanik selalu tetap dengan syarat tidak ada gaya luar yang bekerja pada sistem.
Em1 =Em2
Ep1 + Ek1 = Ep2 + Ek2
m g h1 + ½ mv12 = m g h2 + ½ mv22
Penerapan hukum kekekalan energi mekanik adalah pada kasus benda jatuh dipermukaan bumi atau berada dalam medan gravitasi bumi. Berhubungan dengan hukum kekekalan energi mekanik dapat disimpulkan.
  1. Pada kedudukan awal, kelajuan sama dengan nol sehingga Ek=0, s atau gerak jatuh bebas.  Sedangkan energi potensial Ep mencapai nilai maksimum, sama dengan energi mekaniknya.
  2. Pada keadaan selanjutnya, energi potensial berkurang dan berubah menjadi energi kinetik. Pada setengah perjalananya, besar energi potensial sama dengan energi kinetik.
  3. Pada saat menyentuh tanah (bidang acuan), seluruh energi potensial berubah menjadi energi kinetik sehingga energi potensialnya Ep=0, sedangkan energi kinetik Ek= mencapai nilai maksimum, sama dengan energi mekaniknya.
Energi potensial, energi kinetik serta energi kinetik merupakan besaran skalar sama halnya dengan usaha oleh karena dimensi serta satuannya juga sama.

Demikian posting yang membahas tentang hukum kekekalan energi mekanik, semoga bermanfaat kurang lebihnya tuliskan di kolom komentar.


  1. Kok aku ngitung gituan mumet lagi ya? Wah ... apa harus balik lagi ke SMA?

    1. ga usah balik ke SMA karena tidak akan bisa, waktu hanya berjalan satu arah


  2. Ini tepat sekali untuk adik saya pak. artikel yang dicari para kebanyakan selajar sekarang.

    1. ok terima kasih kalau memang diperlukan

  3. kalo satuannyo apo dio ye??
    tlong di bales kepepet nih

  4. Mkasih yaa :)
    Bgus nih buat nyelesahin tugas

  5. “Energi tidak dapat diciptakan atau dimusnahkan, energi hanya dapat diubah dari satu bentuk ke bentuk lainnya.” Yang pernah di ucapkan salah seorang ahli fisika Inggris, James Prescott Joule.
    ini saya copas dari blog
    dan ini salah satu contohnya.
    Energi kalor dapat dikonversikan ke energi mekanik, kemudian mekanik bisa menciptakan energi lainnya, semisal energi listrik.nah setelah menjadi energi listrik bisa dikasih contoh berubah lagi menjadi energi apalagi?dan menjadi energi apalagi setelahnya?
    terimakasih sebelumnya :)
    bisa minta tlg di email juga ke

  6. apakah bunyi hukum A kekekalan energi B kekekalan mekanik? jwb sekarang :)

  7. kakk makasih banyak yaa postingan fisikanya bermanfaat sekali untuk tugas, ^^ aku ijin salin buat bahan yaaa makasihhh

  8. waah terimakasih yaa. saya terbantu

  9. With spring and summer, it's time to put away the darker clothing like black and dark grays and pull out the brighter clothing. Just as with clothing, the same goes with sunglasses. Put away darker frames, black frame sunglasses, in favor of gold frame or colored frame oakley sunglasses outlet sunglasses.When dressing more casual, choose sunglasses that don't have a metal frame. Oakley makes several pairs of sunglasses that are different colors. For some, one of the hardest looks to pull off is the white frame sunglasses look. A good clothing selection to wear when considering white frame sunglasses is casual oakley sunglasses Khaki pants with a coral polo or an aquamarine polo and flip flops (clothing can be found at Hollister or Dillards). Oakley white rectangle frame sunglasses can be found at Sunglass hut inside the Mall at Turtle Creek.When getting a little more dressed up, choose a pair of gold or brown oakley outlet square framed sunglasses. Ray-Ban, Versace and D&G make several pairs of gold frame sunglasses. A good clothing selection to consider with gold or brown square framed sunglasses is a light tan linen suit with a white button up and an aquamarine tie or a light blue tie (clothing can be found oakleys on sale at Jos. A. Bank or Dillards). Gold or brown frame sunglasses can be found at Sunglass hut and Dillard's inside the Mall at Turtle Creek.
    In 2012, a report said oakley vault that Oakley was working on Google Glass-like smart eyewear.The plan has apparently been in the works for some time. In an interview, Andrea Guerra, chief executive of Luxottica said that the two companies began working together last year. He added, We live in a world where technological innovation has dramatically changed the way in which we communicate and interact in everything that we do. More importantly, we have come to a point where we now oakleys have both a technology push and a consumer pull for wearable technology products and applications. Seeing such a future, over the last years, Luxottica invested heavily in building-out our technology platforms and digital solutions to combine with our products excellence.
    While it is possible to find cheaper sunglasses elsewhere, such as at a kiosk, Sunglass hut and Dillard's carry sunglasses that are excellent quality. Whenever buying something that is good quality, expect to pay a little more. Sure, you could have a cheaper pair of sunglasses for around a month before they fall apart. Why settle for cheaper sunglasses that you will sunglass hut have to replace in a month when you can have a pair of high quality sunglasses that are more expensive that will last you years?With spring in full swing, it’s time to go alfresco and enjoy the longer and warmer days ahead—and get ready to conquer summer with the sleekest, sexiest oakley glasses and sportiest shades around by Oakley.

  10. The “Split Sole” color blocking has helped revitalize the Nike Free Run 2 recently, adding an original touch to the instant classic runner that nike free runs women 5.0 here has the back mesh heel extended in scope to the back of the midsole. The interesting look nike free run 5.0 mens has caught on and today we get a look at the latest colorway, one that boasts a Dark nike free 5.0 girls Obsidian base while the overlays alternate between a Neutral Grey and Orange for an added bit of vibrancy. nike free run 5.0 While a stateside release hasn’t been set just yet, you can catch a better glimpse after the click womens nike free 5.0 green and grab a pair at international retailers like Caliroots today.
    We’re always a fan of when Volt arrives nike free 3.0 v5 atop Flyknit based silhouettes, it’s just curious that this obvious combination didn’t happen sooner with the Nike Free nike free 5.0+ mens Flyknit Chukka. The chukka silhouette has pretty much said goodbye to the lunarlon oustole for the more flexible nike free 2.0 women running standard, while the medial side has ditched the Swoosh branding. Here Fuchsia Flash serves as the accent nike free flyknit 4.0 while black arrives o the branding and the clean midsole swipe. What do you think of the latest nike free 3.0 Flyknit Chukka? We’re still waiting on a stateside release,

  11. We believe that a strategic partnership with a leading player like Google is the ideal platform for developing a new buy ray bans cheap online way forward in our industry and answering the evolving needs of consumers on a global scale. We believe it is high time to combine the unique expertise, deep ray bans eyeglasses knowledge and quality of our Group with the cutting edge technology expertise of Google and give birth to a new generation of revolutionary devices.Radisson Blu wants you to buy ray ban sunglasses see the world through blue-colored glasses at its hotels in Minnesota and Chicago.The brand is providing guests and fans the opportunity to win a pair of blue Ray replica ray bans Ban? Wayfarer? sunglasses when mentioning the winning phrase “Turn My World Blu,” to a staff member seen sporting the shades.
    The tech giant's headset, Google Glass , is Ray Ban Plank wearable technology comprised of a small screen and a wide silver band which keeps the screen within your eye line. Glass can be voice activated to connect to ray ban sun glasses the Web, make calls, access social media and take both photos and videos of what you see.The problem? Besides the hundreds of dollars you will have to pay ray ban p and privacy worries surrounding the device, the headset is frankly ugly.If you want to make a product appealing commercially, then making it attractive helps. Italy's Luxottica, together with ray ban 3025 aviator Google in a "strategic partnership," is an indication that Glass may be given a makeover before hitting the shelves after developers' Explorer program."We believe that a strategic partnership are all ray ban sunglasses polarized with a leading player like Google is the ideal platform for developing a new way forward in our industry and answering the evolving needs of consumers


Bagi adik-adik atau teman-teman pembaca blog ini yang mau kritik atau saran untuk perbaikan blog ini silakan tulis di kotak komentar.
Mohon maaf komentar yang mengandung spam secara otomatis oleh sistem blogger masuk kotak spam atau dihapus