Mohlala oa lipotso tsa katoloso ea sebaka

3 Mehlala ea lipotso mabapi le katoloso ea sebaka

1. Leqephe la tšepe suhu 20^oC e bolelele ba 50 cm le bophara ba 30 cm. Haeba coefficient ea katoloso e otlolohileng ea tšepe e le 10^{-5 o}C^-1 ebe keketseho ea sebaka le sebaka sohle mochesong oa 60^oC ke….

Puisano

Hoa tsebahala hore:

Mocheso oa pele (T)₁= 20^oC

Mocheso oa ho qetela (T)₂= 60^oC

Phetoho ea mocheso (Δ)T) = 60^oC - 20^oEA-40-C^oC

Sebaka sa pele (A)₁) = Bolelele x bophara = 50 cm x 30 cm = 1500 cm²

Coefficient ea katoloso e otlolohileng ea tšepe (α)) = 10^{-5 o}C^-1

Coefficient ea katoloso ea tšepe (β)) = 2a = 2: x 10^{-5 o}C^-1

O botsitse: Keketseho sebakeng (Δ)A)

Karabo:

Keketseho sebakeng (Δ)A):

ΔA = β A_EA-1ΔT

ΔA = (2: x 10^{-5 o}C^-1)(1500 cm²(40)^oC)

ΔA = (80) x 10^-5)(1500 cm²)

ΔA = 120.000: x 10^-5 cm²

ΔA = 1,2: x 10⁵ x 10^-5 cm²

ΔA = 1,2 cm,²

Sebaka sohle (A₂):

A₂ =A₁ +ΔA

A₂ = 1500 XNUMX cm² + 1,2 cm,²

A₂ = 1501,2 cm,²

2. Poleiti ea aluminium e nang le coefficient ea katoloso e otlolohileng ea 24 x 10^-6 /^oC e na le sebaka sa 40 cm² mochesong oa likhato tse 30^oC. Fumana mocheso oa ho qetela haeba sebaka sa poleiti ea aluminium se eketseha ho fihlela ho 40,2 cm².

Puisano

Hoa tsebahala hore:

Mocheso oa pele (T)₁= 30^oC

Coefficient ea katoloso e otlolohileng ea aluminium (α)) = 24: x 10^{-6 o}C^-1

Coefficient ea katoloso ea aluminium (β)) = 2α = 2 x 24 x 10^{-6 o}C^-1 = 48 x 10^{-6 o}C^-1

Sebaka sa pele (A)₁) = 40 cm²

Sebaka sa ho qetela (A)₂) = 40,2 cm²

Phetoho sebakeng (ΔA) = 40,2 cm,² - 40 cm ,.² = 0,2 XNUMX cm²

O botsitse: Fumana mocheso oa ho qetela (T)₂)

Karabo:

Foromo ea phetoho sebakeng (Δ)A) :

ΔA = β A_{1 Δ}T

Mocheso oa ho qetela (T)₂):

ΔA = β A₁ (T₂ - T₁)

0,2 cm,² = (48 x 10^{-6 o}C^-1)(40 cm²)(T₂ - 30^oC)

0,2 = (1920 x 10^-6)(T₂ - 30)

0,2 = (1,920 x 10^-3)(T₂ - 30)

0,2 = (2 x 10^-3)(T₂ - 30)

0,2 / (2 x 10^-3) = T₂ - 30

0,1 x 10³ = T₂ - 30

1: x 10² = T₂ - 30

100 = T₂ - 30

100 + 30 = T₂

T₂ = 130

Mocheso oa ho qetela = 130^oC

3. Ntho e chitja mochesong oa 20^oC e na le radius ea 20 cm. Haeba mochesong oa 100^oC radius e eketseha ho fihla ho 20,5 cm ebe coefficient ea katoloso e otlolohileng ea ntho ke….

Puisano

Hoa tsebahala hore:

Mocheso oa pele (T)₁= 30^oC

Mocheso oa ho qetela (T)₂= 100^oC

Phetoho ea mocheso (Δ)T) = 100^oC - 30^oEA-70-C^oC

Radius ea pele (r)₁) = 20 cm

Radius ea ho qetela (r)₂) = 20,5 cm

O botsitse: Palo e lekanang ea katoloso ea sebaka sa ntho (b)

Karabo:

Sebaka sa pele sa selikalikoe (A₁) = π r₁² = (3,14)(20 cm)² = (3,14)(400 cm²) = 1256 cm²

Sebaka sa ho qetela sa selikalikoe (A₂) = π r₂² = (3,14)(20,5 cm)² = (3,14)(420,25 cm²) = 1319,585 cm²

Keketseho sebakeng sa selikalikoe (ΔA) = 1319,585 cm,² - 1256 cm,² = 63,585 XNUMX cm²

Foromo ea phetoho sebakeng (Δ)A) :

ΔA = β A₁ ΔT

Koefficient ea katoloso ea sebaka:

ΔA = β A₁ ΔT

63,585 cm,² = β (1256 cm,²(70) ^oC)

63,585 = β (87920 ^oC)

β = 63,585 / 87920 ^oC

β = 0,00072 /^oC

β = 7,2 x 10^-4 /^oC

β  = 7,2 x 10^{-4 o}C^-1

Koefficient ea katoloso e otlolohileng (α)):

β = 2 α

α = β / 2

α = (7,2) x 10^-4) / 2

α = 3,6 x 10^{-4 o}C^-1