The incomplete table below shows selected characteristics of gas laws.

Name
Variables
Constants
Equation
?
Pressure, volume
Temperature,
moles of gas
PV = k
Charles’s law
?
?
V = kT
Gay-Lussac’s law
?
?
?
Combined gas law
?
?

What are the variables in Gay-Lussac’s law?
pressure and volume
pressure, temperature, and volume
pressure and temperature
volume, temperature, and moles of gas

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.