Answer:
thickness1=1.4m
thickness2=2.2m
convection coefficient=0.33W/m^2K
Explanation:
you must use this equation to calculate the thickness:
L=K(T2-T1)/Q
L=thickness
T=temperature
Q=heat
L1=0.04*(0--350)/10=1.4m
L2=0.1(220-0)/10=2.2m
Then use this equation to calculate the convective coefficient
H=Q/(T2-T1)
H=10/(250-220)=0.33W/m^2K
Answer:
The break force that must be applied to hold the plane stationary is 12597.4 N
Explanation:
p₁ = p₂, T₁ = T₂
![\dfrac{T_{2}}{T_{1}} = \left (\dfrac{P_{2}}{P_{1}} \right )^{\frac{K-1}{k} }](https://tex.z-dn.net/?f=%5Cdfrac%7BT_%7B2%7D%7D%7BT_%7B1%7D%7D%20%3D%20%5Cleft%20%28%5Cdfrac%7BP_%7B2%7D%7D%7BP_%7B1%7D%7D%20%20%5Cright%20%29%5E%7B%5Cfrac%7BK-1%7D%7Bk%7D%20%7D)
![{T_{2}}{} = T_{1} \times \left (\dfrac{P_{2}}{P_{1}} \right )^{\frac{K-1}{k} } = 280.15 \times \left (9 \right )^{\frac{1.333-1}{1.333} } = 485.03\ K](https://tex.z-dn.net/?f=%7BT_%7B2%7D%7D%7B%7D%20%3D%20T_%7B1%7D%20%5Ctimes%20%5Cleft%20%28%5Cdfrac%7BP_%7B2%7D%7D%7BP_%7B1%7D%7D%20%20%5Cright%20%29%5E%7B%5Cfrac%7BK-1%7D%7Bk%7D%20%7D%20%3D%20280.15%20%5Ctimes%20%5Cleft%20%289%20%20%5Cright%20%29%5E%7B%5Cfrac%7B1.333-1%7D%7B1.333%7D%20%7D%20%3D%20485.03%5C%20K)
The heat supplied =
× Heating value of jet fuel
The heat supplied = 0.5 kg/s × 42,700 kJ/kg = 21,350 kJ/s
The heat supplied =
·
= 20 kg/s
The heat supplied = 20*
= 21,350 kJ/s
= 1.15 kJ/kg
T₃ = 21,350/(1.15*20) + 485.03 = 1413.3 K
p₂ = p₁ × p₂/p₁ = 95×9 = 855 kPa
p₃ = p₂ = 855 kPa
T₃ - T₄ = T₂ - T₁ = 485.03 - 280.15 = 204.88 K
T₄ = 1413.3 - 204.88 = 1208.42 K
![\dfrac{T_5}{T_4} = \dfrac{2}{1.333 + 1}](https://tex.z-dn.net/?f=%5Cdfrac%7BT_5%7D%7BT_4%7D%20%20%3D%20%5Cdfrac%7B2%7D%7B1.333%20%2B%201%7D)
T₅ = 1208.42*(2/2.333) = 1035.94 K
= √(1.333*287.3*1035.94) = 629.87 m/s
The total thrust =
×
= 20*629.87 = 12597.4 N
Therefore;
The break force that must be applied to hold the plane stationary = 12597.4 N.
Answer:
<em>The temperature will be greater than 25°C</em>
Explanation:
In an adiabatic process, heat is not transferred to or from the boundary of the system. The gain or loss of internal heat energy is solely from the work done on the system, or work done by the system. The work done on the system by the environment adds heat to the system, and work done by the system on its environment takes away heat from the system.
mathematically
Change in the internal energy of a system ΔU = ΔQ + ΔW
in an adiabatic process, ΔQ = 0
therefore
ΔU = ΔW
where ΔQ is the change in heat into the system
ΔW is the work done by or done on the system
when work is done on the system, it is conventionally negative, and vice versa.
also W = pΔv
where p is the pressure, and
Δv = change in volume of the system.
In this case,<em> work is done on the gas by compressing it from an initial volume to the new volume of the cylinder. The result is that the temperature of the gas will rise above the initial temperature of 25°C </em>