Roboguru

Sebuah bola yang bermassa 0,1 kg dilempar vertikal...

Sebuah bola yang bermassa 0,1 kg dilempar vertikal ke atas dengan kecepatan awal 10 m/s. Hitunglah :

c. Energi kinetik dan energi potensial bola saat mencapai setengah ketinggian maksimum. 

  1. (...) 

  2. (...) 

Jawaban:

Pada bola terjadi Gerak Vertikal ke atas. Untuk mencari tinggi maksimum, didapatkan perhitungan :

begin mathsize 14px style table attributes columnalign right center left columnspacing 0px end attributes row cell bold italic v subscript bold t to the power of bold 2 bold space end cell bold equals cell bold space bold italic v subscript bold 0 to the power of bold 2 bold space bold minus bold space bold 2 bold italic g bold italic h subscript bold m bold a bold k bold s end subscript end cell row cell open parentheses 0 close parentheses squared space end cell equals cell space open parentheses 10 space straight m divided by straight s close parentheses squared space minus space 2 space open parentheses 10 space straight m divided by straight s squared close parentheses space h subscript m a k s end subscript end cell row cell 0 space end cell equals cell space 100 space minus space 20 space h subscript m a k s end subscript end cell row cell 20 space h subscript m a k s end subscript space end cell equals cell space 100 end cell row cell h subscript m a k s end subscript space end cell equals cell space 100 over 20 end cell row cell bold italic h subscript bold italic m bold italic a bold italic k bold italic s end subscript bold space end cell bold equals cell bold space bold 5 bold space bold m end cell end table end style 

Setengah ketinggian maksimum, yaitu :

begin mathsize 14px style table attributes columnalign right center left columnspacing 0px end attributes row cell h space end cell equals cell space 1 half space h subscript m a k s end subscript end cell row cell h space end cell equals cell space 1 half space open parentheses 5 space straight m close parentheses space equals space bold 2 bold comma bold 5 bold space bold meter end cell end table end style 

Energi Potensial bola saat mencapai setengah ketinggian maksimum

begin mathsize 14px style table attributes columnalign right center left columnspacing 0px end attributes row cell bold italic E subscript bold italic p bold space end cell bold equals cell bold space bold italic m bold italic g bold italic h end cell row cell E subscript p space end cell equals cell space 0 comma 1 space kg space times space 10 space straight m divided by straight s squared space times space 2 comma 5 space straight m end cell row cell E subscript p space end cell equals cell bold space bold 2 bold comma bold 5 bold space bold J end cell end table end style 

Besarnya Energi Kinetik bola saat mencapai setengah ketinggian maksimum dicari menggunakan Hukum Kekekalan Energi Mekanik

begin mathsize 14px style table attributes columnalign right center left columnspacing 0px end attributes row cell bold italic E subscript bold italic k bold 1 end subscript bold space bold plus bold space bold italic E subscript bold italic p bold 1 end subscript bold space end cell bold equals cell bold space bold italic E subscript bold italic k bold 2 end subscript bold space bold plus bold space bold italic E subscript bold italic p bold 2 end subscript end cell row cell 5 space straight J space plus space 0 space end cell equals cell space E subscript k 2 end subscript space plus space 2 comma 5 space straight J end cell row cell 5 space straight J space end cell equals cell space E subscript k 2 end subscript space plus space 2 comma 5 space straight J end cell row cell E subscript k 2 end subscript space end cell equals cell space 5 space straight J space minus space 2 comma 5 space straight J end cell row cell bold italic E subscript bold italic k bold 2 end subscript bold space end cell bold equals cell bold space bold 2 bold comma bold 5 bold space bold J end cell end table end style 

Jadi, saat bola mencapai setengah ketinggian maksimum besarnya energi kinetik dan energi potensial adalah 2,5 J.   

0

Ruangguru

RUANGGURU HQ

Jl. Dr. Saharjo No.161, Manggarai Selatan, Tebet, Kota Jakarta Selatan, Daerah Khusus Ibukota Jakarta 12860

Coba GRATIS Aplikasi Ruangguru

Produk Ruangguru

Produk Lainnya

Hubungi Kami

Ikuti Kami

©2021 Ruangguru. All Rights Reserved