An igneous rock floats because air bubbles became trapped when molten material erupted from an underground volcano. How els can this rock be accurately describe?

it should have an internal chamber and two thermometers sticking out of the top. the internal chamber will also be closed off from the outside.

answer: semi-infinite solid initially at a uniform temperature of 400 ◦c is cooled at its surface by convection. the cooling fluid at a constant temperature of 200 ◦c has a convective coefficient (ha) of 250 w/m2.k. the physical properties of the solid: k = 20 w/m.k and α = 4 * 10-5  m2/s. using δx = 0.04 m and δt = 10 s. write the finite difference equations describing the transient heat transfer of the first five δx and the temperature profile after 30 s.

wanswer:

explanation: