http://file.upi.edu/Direktori/DUAL- MODES/KONSEP_DASAR_FISIKA/BBM_5_%28Pesa wat_Sederhana%29_KD_Fisika.pdf https://www.youtube.com/watch? v=QzZJSGFTt30&t=267s https://www.youtube.com/watch?v=C7RwpAVf7dw 54