Answer:
Explanation:
Mean temperature is given by

Tmean = (Ti + T∞)/2

Tmean = 107.5⁰C
Tmean = 107.5 + 273 = 380.5K
Properties of air at mean temperature
v = 24.2689 × 10⁻⁶m²/s
α = 35.024 × 10⁻⁶m²/s
= 221.6 × 10⁻⁷N.s/m²
= 0.0323 W/m.K
Cp = 1012 J/kg.K
Pr = v/α = 24.2689 × 10⁻⁶/35.024 × 10⁻⁶
= 0.693
Reynold's number, Re
Pv = 4m/πD²
where Re = (Pv * D)/
Substituting for Pv
Re = 4m/(πD
)
= (4 x 0.003)/( π × 6 ×10⁻³ × 221.6 × 10⁻⁷)
= 28728.3
Since Re > 2000, the flow is turbulent
For turbulent flows, Use
Dittus - Doeltr correlation with n = 0.03
Nu = 0.023Re⁰⁸Pr⁰³ = (h₁D)/k
(h₁ × 0.006)/0.0323 = 0.023(28728.3)⁰⁸(0.693)⁰³
(h₁ × 0.006)/0.0323 = 75.962
h₁ = (75.962 × 0.0323)/0.006
h₁ = 408.93 W/m².K
Mass affects the weight of an airplane because everything has mass
Answer:
The rise in temperature of helium gas is 14.25 K.
Explanation:
Given that
H= 4.5 km
The box is insulated ,at 4.5 km height helium gas have potential energy and when it come down then this potential energy will convert into the internal energy of helium gas.
So by heat balance


for helium gas
Now by putting the values

10 x 4.5 =3.15 x ΔT
ΔT=14.25 K
So the rise in temperature of helium gas is 14.25 K.
Explanation: A Constant Volume Forced Air system is a form of a mechanical system that is considered the most basic type of system. It is most common in use and high yielding in the application