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
Mineral wool, k = 0.04100 mm23 °C-4 °CQ̇ = ?

A wall of mineral wool is 100 mm thick and has an area of 15 m². Its faces are held at 23 °C and -4 °C. Find the rate of heat conduction Q̇ through the wall.

k = 0.04 W/(m·K)L = 100 mmA = 15 m²T1 = 23 °CT2 = -4 °C
Q̇ = W
2.Easy
Concrete, k = 1.4250 mm24 °C-7 °CQ̇ = ?

A wall of concrete is 250 mm thick and has an area of 12 m². Its faces are held at 24 °C and -7 °C. Find the rate of heat conduction Q̇ through the wall.

k = 1.4 W/(m·K)L = 250 mmA = 12 m²T1 = 24 °CT2 = -7 °C
Q̇ = W
3.Medium
Brick, k = 0.7250 mmGlass, k = 0.96150 mm23 °C2 °CTi​ = ?Q̇

A wall is made of 50 mm of brick and 150 mm of glass, with an area of 15 m². The outer faces are at 23 °C and 2 °C. Find the temperature Ti at the interface between the two layers.

L1 = 50 mm, k1 = 0.72 W/(m·K)L2 = 150 mm, k2 = 0.96 W/(m·K)A = 15 m²T1 = 23 °CT3 = 2 °C
Ti = °C
4.Medium
Gypsum board, k = 0.17150 mmConcrete, k = 1.4150 mm22 °C-2 °CTi​ = ?Q̇

A wall is made of 150 mm of gypsum board and 150 mm of concrete, with an area of 8 m². The outer faces are at 22 °C and -2 °C. Find the temperature Ti at the interface between the two layers.

L1 = 150 mm, k1 = 0.17 W/(m·K)L2 = 150 mm, k2 = 1.4 W/(m·K)A = 8 m²T1 = 22 °CT3 = -2 °C
Ti = °C
5.Hard
Glass, k = 0.9650 mmExpanded polystyrene, k = 0.03550 mmroom 21 °Coutside -12 °CTs​ = ?Q̇

A wall of 50 mm glass and 50 mm expanded polystyrene separates a room at 21 °C from outside air at -12 °C. The convection coefficients are 10 W/(m²·K) inside and 25 W/(m²·K) outside, and the wall area is 6 m². Find the temperature Ts of the inside surface of the wall.

L1 = 50 mm, k1 = 0.96 W/(m·K)L2 = 50 mm, k2 = 0.035 W/(m·K)A = 6 m²hi = 10 W/(m²·K)ho = 25 W/(m²·K)Troom = 21 °CTout = -12 °C
Ts = °C
6.Hard
Wood, k = 0.17200 mmMineral wool, k = 0.04100 mmroom 22 °Coutside -5 °CTs​ = ?Q̇

A wall of 200 mm wood and 100 mm mineral wool separates a room at 22 °C from outside air at -5 °C. The convection coefficients are 10 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 = 0.17 W/(m·K)L2 = 100 mm, k2 = 0.04 W/(m·K)A = 20 m²hi = 10 W/(m²·K)ho = 25 W/(m²·K)Troom = 22 °CTout = -5 °C
Ts = °C

Answer key

  1. 1. Q̇ = 162 W
  2. 2. Q̇ = 2083 W
  3. 3. Ti = 16.54 °C
  4. 4. Ti = 0.5987 °C
  5. 5. Ts = 18.96 °C
  6. 6. Ts = 21.29 °C

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