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
Wood, k = 0.1710 mm19 °C4 °Cq″ = ?

A wall of wood is 10 mm thick and has an area of 8 m². Its faces are held at 19 °C and 4 °C. Find the heat flux q″ through the wall.

k = 0.17 W/(m·K)L = 10 mmA = 8 m²T1 = 19 °CT2 = 4 °C
q″ = W/m²
2.Easy
Brick, k = 0.7250 mm22 °C-15 °CQ̇ = ?

A wall of brick is 50 mm thick and has an area of 6 m². Its faces are held at 22 °C and -15 °C. Find the rate of heat conduction Q̇ through the wall.

k = 0.72 W/(m·K)L = 50 mmA = 6 m²T1 = 22 °CT2 = -15 °C
Q̇ = W
3.Medium
Wood, k = 0.17200 mmMineral wool, k = 0.0450 mm18 °C9 °CQ̇ = ?

A wall is made of 200 mm of wood and 50 mm of mineral wool, with an area of 6 m². The outer faces are at 18 °C and 9 °C. Find the heat flow Q̇ through the wall.

L1 = 200 mm, k1 = 0.17 W/(m·K)L2 = 50 mm, k2 = 0.04 W/(m·K)A = 6 m²T1 = 18 °CT3 = 9 °C
Q̇ = W
4.Medium
Glass, k = 0.96100 mmGypsum board, k = 0.1725 mm24 °C-5 °CTi​ = ?Q̇

A wall is made of 100 mm of glass and 25 mm of gypsum board, with an area of 4 m². The outer faces are at 24 °C and -5 °C. Find the temperature Ti at the interface between the two layers.

L1 = 100 mm, k1 = 0.96 W/(m·K)L2 = 25 mm, k2 = 0.17 W/(m·K)A = 4 m²T1 = 24 °CT3 = -5 °C
Ti = °C
5.Hard
Glass, k = 0.96150 mmGypsum board, k = 0.1775 mmroom 22 °Coutside 5 °CTs​ = ?Q̇

A wall of 150 mm glass and 75 mm gypsum board separates a room at 22 °C from outside air at 5 °C. The convection coefficients are 10 W/(m²·K) inside and 20 W/(m²·K) outside, and the wall area is 6 m². Find the temperature Ts of the inside surface of the wall.

L1 = 150 mm, k1 = 0.96 W/(m·K)L2 = 75 mm, k2 = 0.17 W/(m·K)A = 6 m²hi = 10 W/(m²·K)ho = 20 W/(m²·K)Troom = 22 °CTout = 5 °C
Ts = °C
6.Hard
Concrete, k = 1.450 mmGlass, k = 0.9650 mmroom 21 °Coutside 5 °CTs​ = ?Q̇

A wall of 50 mm concrete and 50 mm glass separates a room at 21 °C from outside air at 5 °C. The convection coefficients are 8 W/(m²·K) inside and 20 W/(m²·K) outside, and the wall area is 10 m². Find the temperature Ts of the inside surface of the wall.

L1 = 50 mm, k1 = 1.4 W/(m·K)L2 = 50 mm, k2 = 0.96 W/(m·K)A = 10 m²hi = 8 W/(m²·K)ho = 20 W/(m²·K)Troom = 21 °CTout = 5 °C
Ts = °C

Answer key

  1. 1. q″ = 255 W/m²
  2. 2. Q̇ = 3197 W
  3. 3. Q̇ = 22.25 W
  4. 4. Ti = 11.98 °C
  5. 5. Ts = 19.73 °C
  6. 6. Ts = 13.39 °C

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