Jawabanmu

2014-02-02T13:10:16+07:00
Dik : f = 10 cm  ; s' = 2s
Dit : s = ...
Jawab :
1/s = 1/f - 1/s
maaf belum seleai salah klik
selanjutnya 1/s = 1/f - 1/s'
1/s = 1/10 - 1/2s -----> 1/s + 1/2s = 1/10 ----> 2/2s + 1/2s = 10
3/2s = 1/10 jadi 2s = 30 maka s = 15 cm