Jawabanmu

2014-03-01T06:22:48+07:00
Lt =  L_{0} x α x ΔT
= 20 x 0,00002 x 50
= 0,02 cm
2014-03-01T11:49:15+07:00
Dik : L = 40 cm
Δ t = 70 C - 20 C = 50 C
α = 0,00002/C
Dit : L baja...?
jwb :
L baja = Lo (1 + α. Δt)
= 40 ( 1 + 0,00002 . 50) = 40 ( 1 + 0.001)=40,04 cm