Heat conduction worksheet with answers

Free printable Heat conduction worksheet: 6 problems from easy to exam level, with an answer key. Print it or save it as a PDF.

New worksheetPractise online with hints

For teachers: free to print, copy and use in class. Every new worksheet has new values and its own answer key. A link to ExamProblems on your course page is appreciated.

Name: ____________________   Date: ____________

1.Easy
Glass, k = 0.9650 mm25 °C10 °CQ̇ = ?

A wall of glass is 50 mm thick and has an area of 20 m². Its faces are held at 25 °C and 10 °C. Find the rate of heat conduction Q̇ through the wall.

k = 0.96 W/(m·K)L = 50 mmA = 20 m²T1 = 25 °CT2 = 10 °C
Q̇ = W
2.Easy
Mineral wool, k = 0.0450 mm16 °C5 °Cq″ = ?

A wall of mineral wool is 50 mm thick and has an area of 12 m². Its faces are held at 16 °C and 5 °C. Find the heat flux q″ through the wall.

k = 0.04 W/(m·K)L = 50 mmA = 12 m²T1 = 16 °CT2 = 5 °C
q″ = W/m²
3.Medium
Gypsum board, k = 0.17100 mmWood, k = 0.1750 mm17 °C-11 °CTi​ = ?Q̇

A wall is made of 100 mm of gypsum board and 50 mm of wood, with an area of 6 m². The outer faces are at 17 °C and -11 °C. Find the temperature Ti at the interface between the two layers.

L1 = 100 mm, k1 = 0.17 W/(m·K)L2 = 50 mm, k2 = 0.17 W/(m·K)A = 6 m²T1 = 17 °CT3 = -11 °C
Ti = °C
4.Medium
Glass, k = 0.96100 mmConcrete, k = 1.450 mm22 °C-2 °CQ̇ = ?

A wall is made of 100 mm of glass and 50 mm of concrete, with an area of 20 m². The outer faces are at 22 °C and -2 °C. Find the heat flow Q̇ through the wall.

L1 = 100 mm, k1 = 0.96 W/(m·K)L2 = 50 mm, k2 = 1.4 W/(m·K)A = 20 m²T1 = 22 °CT3 = -2 °C
Q̇ = W
5.Hard
Concrete, k = 1.4200 mmMineral wool, k = 0.0425 mmroom 20 °Coutside -4 °CTs​ = ?Q̇

A wall of 200 mm concrete and 25 mm mineral wool separates a room at 20 °C from outside air at -4 °C. The convection coefficients are 8 W/(m²·K) inside and 25 W/(m²·K) outside, and the wall area is 20 m². Find the temperature Ts of the inside surface of the wall.

L1 = 200 mm, k1 = 1.4 W/(m·K)L2 = 25 mm, k2 = 0.04 W/(m·K)A = 20 m²hi = 8 W/(m²·K)ho = 25 W/(m²·K)Troom = 20 °CTout = -4 °C
Ts = °C
6.Hard
Expanded polystyrene, k = 0.035100 mmConcrete, k = 1.475 mmroom 20 °Coutside -7 °CQ̇ = ?

A wall of 100 mm expanded polystyrene and 75 mm concrete separates a room at 20 °C from outside air at -7 °C. The convection coefficients are 6 W/(m²·K) inside and 25 W/(m²·K) outside, and the wall area is 20 m². Find the heat loss Q̇ through the wall.

L1 = 100 mm, k1 = 0.035 W/(m·K)L2 = 75 mm, k2 = 1.4 W/(m·K)A = 20 m²hi = 6 W/(m²·K)ho = 25 W/(m²·K)Troom = 20 °CTout = -7 °C
Q̇ = W

Answer key

  1. 1. Q̇ = 5760 W
  2. 2. q″ = 8.8 W/m²
  3. 3. Ti = −1.667 °C
  4. 4. Q̇ = 3431 W
  5. 5. Ts = 16.78 °C
  6. 6. Q̇ = 173.2 W

Full step-by-step solutions: practise this topic on examproblems.com.