Answer:
a) The exit temperature is 430 K
b) The inlet and exit areas are 0.0096 m² and 0.051 m²
Explanation:
a) Given:
T₁ = 127°C = 400 K
At 400 K, h₁ = 400.98 kJ/kg (ideal gas properties table)
The energy equation is:
For a diffuser, w = Δp = 0
The diffuser is adiabatic, q = 0
Replacing:
Where
V₁ = 250 m/s
V₂ = 40 m/s
Replacing:
Using tables, at 431.43 kJ/kg the temperature is 430 K
b) The inlet area is:
The exit area is:
Answer:
D. Banks and offices closing on sunday.
Explanation:
Church is usually on sunday and people need a day off to do it because service is about 3 hours long. When banks and offices close on this day it shows how religion has affected our lives and our culture.
Answer:
Explanation:
a )
Amplitude A = 14 mm , angular frequency ω = 2π / T
= 2π / .5
ω = 4π rad /s
φ₀ = initial phase
Putting the given values in the equation
14 = 25 cos(ωt + φ₀ )
14/25 = cosφ₀
φ₀ = 56 degree
x(t) = 25cos(4πt + 56° )
b )
maximum velocity = ω A
= 4π x 25
100 x 3.14 mm /s
= 314 mm /s
At x = 0 ( equilibrium position or middle point , this velocity is achieved. )
maximun acceleration = ω² A
= 16π² x A
= 16 x 3.14² x 25
= 3943.84 mm / s²
3.9 m / s²
It occurs at x = A or at extreme position.
Answer:
B
Explanation:
A square of frequency of consists of the infinite sum of sine waves, whose frequencies are the odd multiples of the main frequency f i.e f, 3f,5f, 7f, ... . Given that the range of frequencies, to which the system responds is 20-40 kHz, for a square wave of frequency 10kHz we need to look for the harmonics whose frequencies are in the systems' respond range, which are the harmonics of 20, 30 and 40 kHz
