Athick wood slab = 0.2 w/m. k and = 1.28 × 10−7 m2 /s) that is initially at a uniform temperature of 25°c is exposed to hot gases at 550°c for a period of 300 sec. as a results of the process, the wood slab is continuously being heated supplied with a heat flux of 13 kw/m2 . if the ignition temperature of wood is 450°c, determine if the wood will ignite.

How is coal extracted from mountaintop removal mines? a. dynamite is used to create underground tunnels where miners go to extract the coal. b. dynamite is used to break apart rocks and then draglines are used to remove the broken rock and reach the coal. c. coal in mountaintops is extracted by digging strips in the landscape to reach the coal. d. placer deposits in mountain river bottoms are removed by

What is the thinnest soap film (excluding the case of zero thickness) that appears black when illuminated with light with a wavelength of 480 ? the index of refraction of the film is 1.34, and there is air on both sides of the film. express your answer in nanometers. hint 1. how to approach th

Difference between series and parallel circuits