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
Expanded polystyrene, k = 0.035150 mm23 °C7 °CQ̇ = ?

A wall of expanded polystyrene is 150 mm thick and has an area of 15 m². Its faces are held at 23 °C and 7 °C. Find the rate of heat conduction Q̇ through the wall.

k = 0.035 W/(m·K)L = 150 mmA = 15 m²T1 = 23 °CT2 = 7 °C
Q̇ = W
2.Easy
Brick, k = 0.7220 mm17 °C-8 °CQ̇ = ?

A wall of brick is 20 mm thick and has an area of 12 m². Its faces are held at 17 °C and -8 °C. Find the rate of heat conduction Q̇ through the wall.

k = 0.72 W/(m·K)L = 20 mmA = 12 m²T1 = 17 °CT2 = -8 °C
Q̇ = W
3.Medium
Wood, k = 0.17200 mmGlass, k = 0.9650 mm17 °C9 °CQ̇ = ?

A wall is made of 200 mm of wood and 50 mm of glass, with an area of 8 m². The outer faces are at 17 °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 = 0.96 W/(m·K)A = 8 m²T1 = 17 °CT3 = 9 °C
Q̇ = W
4.Medium
Gypsum board, k = 0.17150 mmWood, k = 0.1750 mm23 °C4 °CQ̇ = ?

A wall is made of 150 mm of gypsum board and 50 mm of wood, with an area of 10 m². The outer faces are at 23 °C and 4 °C. Find the heat flow Q̇ through the wall.

L1 = 150 mm, k1 = 0.17 W/(m·K)L2 = 50 mm, k2 = 0.17 W/(m·K)A = 10 m²T1 = 23 °CT3 = 4 °C
Q̇ = W
5.Hard
Brick, k = 0.7250 mmGypsum board, k = 0.17150 mmroom 20 °Coutside -11 °CQ̇ = ?

A wall of 50 mm brick and 150 mm gypsum board separates a room at 20 °C from outside air at -11 °C. The convection coefficients are 7.7 W/(m²·K) inside and 30 W/(m²·K) outside, and the wall area is 12 m². Find the heat loss Q̇ through the wall.

L1 = 50 mm, k1 = 0.72 W/(m·K)L2 = 150 mm, k2 = 0.17 W/(m·K)A = 12 m²hi = 7.7 W/(m²·K)ho = 30 W/(m²·K)Troom = 20 °CTout = -11 °C
Q̇ = W
6.Hard
Mineral wool, k = 0.04100 mmWood, k = 0.1725 mmroom 22 °Coutside -4 °CQ̇

A wall of 100 mm mineral wool and 25 mm wood separates a room at 22 °C from outside air at -4 °C. The convection coefficients are 10 W/(m²·K) inside and 20 W/(m²·K) outside, and the wall area is 4 m². Find the overall heat transfer coefficient U of the wall.

L1 = 100 mm, k1 = 0.04 W/(m·K)L2 = 25 mm, k2 = 0.17 W/(m·K)A = 4 m²hi = 10 W/(m²·K)ho = 20 W/(m²·K)Troom = 22 °CTout = -4 °C
U = W/(m²·K)

Answer key

  1. 1. Q̇ = 56 W
  2. 2. Q̇ = 10800 W
  3. 3. Q̇ = 52.09 W
  4. 4. Q̇ = 161.5 W
  5. 5. Q̇ = 333.6 W
  6. 6. U = 0.3575 W/(m²·K)

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