# Question #97470

##### 1 Answer

It is clear that the slab of steel at

#"Total heat lost by the steel slab"=mst#

where#m# is mass of slab,#s# specific heat of steel and#t# is change in its temperature.

Assuming density

-.-.-.-.-.-.-.-.-.-.-.-.-.-.

A. Now, rate of heat loss due to conduction

Lets assume that the

Deck is at temperature of surroundings

The heat loss from top to bottom of slab is found by taking

Area

Thermal conductivity

We know that basic conduction problem equation is

#dot Q=(kAΔT)/"thickness of slab"#

Inserting above values we get

B. Similarly basic convection problem equation is

basic equation for convection,

#dotQ=hAΔT#

where heat transfer coefficient#h=10Wm^-2K^-1# .

Area

Inserting above values we get

C. For radiation loss we have Stefan-Boltzmann Law.

#dotQ=εAσ(T_1^4– T_2^4)#

where#sigma# is the Stefan Boltzmann constant#= 5.670367 xx 10^-8 Wm^-2 K^-4# ,#T_1K# is temperature of radiating body and#T_2K# is temperature of surroundings.

We are given the emissivity for steel,

Inserting given values we get

D. Total heat loss rate

Assuming rate of heat loss via each mode is constant throughout the time of loss.

Heat lost via conduction