Question

10 pontos
Um bloco de aluminio de
coeficiente de dilatação linear 24.
10-6 tem volume de 40 cm3 a 10 °C
Determine a temperatura na qual
seu volume fica igual a 40,144 cm3.
80 °C
60 °C
70 °C
50 °C
40 °C

Answer 1

to = 10°

t = ?

a = 3×24. 10^-6 = 72 . 10^-6

Vo = 40cm^3

v = 40,144 cm^3

Δv = 40,144 - 40 = 0,144 m^3

Δv = Vo . a . (t - to )

0,144 = 40. 72.10^-6 . ( t - 10)

0,144 = 2880 . 10^6 . (t - 10)

0,144 = 0.00288 . ( t - 10)

0,144 = 0,00288t- 0,0288

0,1728 = 0,00288t

t = 60° (Resposta)

Answer 2

Δv = vο × γ × ( Tf - Ti )

Δv = 40,144 - 40

Δv = 0,144

vο = 40

γ = 3 × $24.10^{-6}$

γ = $72.10^{-6}$

Tf = ?????

Ti = 10

0,144 = 40 × $72.10^{-6}$ × ( Tf - 10 )

0,144 = ( 40 × 72 ).$10^{-6}$ × ( Tf - 10 )

0,144 = $2880.10^{-6}$ × ( Tf - 10 )

0,144 = $2,880.10^{-3}$ × ( Tf - 10 )

0,144 = 0,002880 × Tf  ( 0,002880 × - 10 )

0,144 =  0,002880 × Tf - 0,0288

0,144 + 0,0288 = 0,002880 × Tf

0,1728 = 0,002880 × Tf

$\frac{0,1728}{0,002880}$ = Tf

60 = Tf

Tf = 60°C