Answer:
T = 858.25 s
Explanation:
Given data:
Reheat stage for a 100-mm-thick steel plate ( 7830 kg/m3, c 550 J/kg K, k 48 W/m K),
initial uniform temperature ( Ti ) = 200 c
Final temperature = 550 c
convection coefficient = 250 w/m^2 k
products combustion temp = 800 c
calculate how long the plate should be left in the furnace ( to attain 550 c )
first calculate/determine the Fourier series Number ( Fo )
= 0.4167 = 
therefore Fo = 3.8264
Now determine how long the plate should be left in the furnace
Fo = 
k = 48
p = 7830
L = 0.1
Input the values into the relation and make t subject of the formula
hence t = 858.25 s
D make your car easy to spot in daytime because they do not illuminate a lot
Because of the skin depth effect, the current at high frequency tends to flow at very low depth from radius. Then at high frequency the effective cross section of the wire is narrower than at DC.
Fro example skin depth at 100 kHz is 0.206 mm (0.008”), a wire more thicker than AWG26 could be a waste of copper, better use a bunch of thin wire (Litz wire) to rise the Q factor.
Answer:
A)
It should be Non- toxic
It should possess high Thermal conductivity
It should have the Required Thermal diffusivity
B)
- stoneware : This material has good thermal diffusivity and it is quite affordable and it is used in making pizza stones
- porcelain: mostly used for mugs and it is non-toxic
- Pyrex : posses good thermal conductivity used in oven
C) All the materials are suitable because they serve different purposes when making modern kitchen cookware
Explanation:
A) characteristics required of a ceramic material to be used as a kitchen cookware
- It should be Non- toxic
- It should possess high Thermal conductivity
- It should have the Required Thermal diffusivity
B) comparison of three ceramic materials as to their relative properties
- stoneware : This material has good thermal diffusivity and it is quite affordable and it is used in making pizza stones
- porcelain: mostly used for mugs and it is non-toxic
- Pyrex : posses good thermal conductivity used in ovens
C) material most suitable for the cookware.
All the materials are suitable because they serve different purposes when making modern kitchen cookware
