Jawabanmu

2014-05-15T21:06:25+07:00
Δl = α × l1 × ΔT
= 0.000011 × 5 × (80-30)
= 0,000011 × 5 × 50
= 0,00275 

l2 = l1 + Δl
= 5 + 0,00275 
= 5,00275 cm

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