kak bantuin please no.9 dan 10...

Nomor 9
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fob = 100 cm
M min = 20 kali
Tanya :
Jarak lensa obyektif dan okuler, d = ___?

Jawab :
Step 1
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Cari fok = ___?
M min = fob / fok
20 = 100 / fok
fok = 50 cm

Step 2
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Cari d = __?
d = fob + fok
d = 100 + 50
d = 150 cm

Nomor 10
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Suhu awal, T1 = 45 derajat C
Suhu akhir, T2 = 85 derajat C
Beda suhu, delta T = T2 - T1 = 85 - 45 = 40 derajat C

Panjang akhir, L = 50,02 cm
Koef muai panjang, alfa = 1 x 10^-5 / derajat C

Tanya :
Panjang awal baja, Lo = ___?

Jawab :


L = Lo.(1 + alfa. Delta T)

50,02 = Lo.(1 + 10^-5. 40)
50,02 = Lo.(1 + 4.10^-4)
50,02 = Lo.(1 + 0,0004)
50,02 = Lo.(1,0004)

Lo = 50,02 / 1,0004

Lo = 50 cm

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