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.

answer: option c. i.e. electric current flowing “downhill” from the negative electrode to the positive electrode in a battery

explanation:

the water analogy to the circuits define the pipes (water flows) to the electric current. now, we know that the electric current flows from the positive terminal to the circuit (as shown in the diagram attached).

hence, option c is the correct answer.

do you have a formula possibly