Sebuah benda diletakkan 60 cm didepan cermin jika tinggi benda tersebut 3cm dan focus cermin cekung 15 cm tentukan Letak bayangan Perbesaran bayangan Tinggi

pemantulan cahaya

cermin cekung
f = 15 cm
s = 60 cm ... ruang 3
h = 3 cm

a][ jarak bayangan
1/s + 1/s' = 1/f
1/60 + 1/s' = 1/15
1/s' = 1/15 - 1/60
1/s' = 4/60 - 1/60
1/s' = 3/60
s' = 60/3 = 20 cm ✔️
(ruang 2)

b][ perbesaran
m = a' / s
m = 20 / 60
m = ⅓ kali ✔️

c][ tinggi bayangan
h' = m h
h' = ⅓ • 3
h' = 1 cm ✔️


atau

perbesaran
m = f / (s - f)
m = 15 / (60 - 15) = 15/45 = ⅓

jarak bayangan
s' = m s = ⅓ • 60 = 20 cm

tinggi bayangan
h' = m h = ½ • 3 = 1 cm