Conduction: A solid concrete wall has dimensions 4.0 m × 2.4 m and is 30 cm thick. The thermal conductivity of the concrete is 1.3 W/m ? K, and it separates a basement from the ground outside. The inner surface of the wall is at 18°C, and the outside surface is at 6°C. How much heat flows through the wall every hour?
A. 1.8 MJ
B. 1.8 kJ
C. 500 J
D. 5.0 MJ
E. 5.0 kJ
Answer: A
You might also like to view...
How long ago did multicellular life forms appear in the fossil record?
A) 4.5 billion years ago B) 3.8 billion years ago C) one billion years ago D) 63 million years ago E) 30 million years ago
Which of the following processes is due to
convection? a) The flowing of air from over cool water toward a warmer land area. b) The warming of the interior of a closed auto on a hot, sunny day. c) The frying of eggs in a hot pan. d) The direct warming of the Earth’s surface by the energy from the Sun.
For the following balanced reaction, which of the following is a gas?
2 Na(l) + Cl2(g) ? 2 NaCl(s) A) Na B) 2 Na C) Cl2 D) Cl E) NaCl
How are mass and weight different?
A. Weight is the amount of matter an object contains; mass is the type of matter an object is made of. B. Mass is the amount of matter an object contains; weight is how much mass an object contains. C. Weight is a measure of how much gravity pulls an object; mass is how much matter the object has. D. There is no difference; they are the same.