Sebuah benda bercahaya dengan tinggi 2 cm berada 30 cm didepan cermin cekung. Jari jari cermin tersebut 45cm tentukanlah jarak bayangan, tinggi bayangan dan pe

Ho = 2 cm
So = 30 cm
R = 45 cm

f = ½R
= ½ 45
= 22,5 cm

Jarak bayangan (Si)
1/Si = 1/So - 1/f = 90 cm

Perbesaran bayangan (M)
M = Si/So = 3 kali

Tinggi bayangan (Hi)
Hi = M × Ho = 6 cm



GL!

Diket : h = 2 cm
s = 30 cm
R = 45 cm
Dit :
s' = ...?
h' = ...?
M = ...?
Jawab
1/f = 1/s + 1/s'
1/22,5= 1/30 + 1/s'
1/s' = 1/22,5 - 1/30
1/s' = 4-3/90
1/s' = 1/90
s' = 90 cm. Jadi, jarak bayangan 90 cm

M = s'/s
M = 90/30
M = 3. jadi perbesarannya 3 kali

M = h'/h
3 = h'/2
h' = 3 × 2 = 6 cm. jadi tinggi bayangan 6 cm