Jawaban:

Diketahui:

R = 2f = 20 cm

f = 20/2 = 10 cm

h = 5 cm

Ditanya:

h' jika:

a. s = 5 cm

b. s = 15 cm

c. s = 20 cm

d. s = 30 cm

DIjawab:

a.

1/f = 1/s + 1/s'

1/10 = 1/5 + 1/s'

1/10 - 1/5 = 1/s'

1/10 - 2/10 = 1/s'

-1/10 = 1/s'

s' = -10 cm

h'/h = s'/s

h'/5 = -10/5

h' = 5x-10/5 = -10 cm

Tinggi bayangan = 10 cm (tegak)

b.

1/f = 1/s + 1/s'

1/10 = 1/15 + 1/s'

1/10 - 1/15 = 1/s'

3/30 - 2/30 = 1/s'

1/30 = 1/s'

s' = 30 cm

h'/h = s'/s

h'/5 = 30/15

h' = 5x30/15 = 10 cm (bayangan terbalik)

c.

1/f = 1/s + 1/s'

1/10 = 1/20 + 1/s'

1/10 - 1/20 = 1/s'

2/20 - 1/20 = 1/s'

1/20 = 1/s'

s' = 20 cm

h'/h = s'/s

h'/5 = 20/20

h' = 5x20/20 = 5 cm (bayangan terbalik)

d.

1/f = 1/s + 1/s'

1/10 = 1/30 + 1/s'

1/10 - 1/30 = 1/s'

3/30 - 1/30 = 1/s'

2/30 = 1/s'

s' = 15 cm

h'/h = s'/s

h'/5 = 15/30

h' = 5x15/30 = 2,5 cm (bayangan terbalik)