I’ve been feeeling very lonely
Answer:
7 benefits of a car: What you should know
Health and Emergencies. The safest way to ensure your health in the pandemic is by owning a private car. ...
Independence and Freedom. Relying on others for travel or using public vehicles could be detrimental. ...
Privacy. ...
Safety. ...
Save Time. ...
Take Pleasure Trips. ...
Flexibility.
Explanation:
The modern negative consequences of heavy automotive use include the use of non-renewable fuels, a dramatic increase in the rate of accidental death, the disconnection of local community, the decrease of local economy, the rise in obesity and cardiovascular diseases, the emission of air and noise pollution, the ...
Answer:
Qin = 1857 kJ
Explanation:
Given
m = 0.5 Kg
T₁ = 25°C = (25 + 273) K = 298 K
P₁ = 100 kPa
P₂ = 500 kPa
First, the temperature when the piston starts rising is determined from the ideal gas equations at the initial state and at that state:
T₂ = T₁*P₂/P₁
⇒ T₂ = 298 K*(500 kPa/100 kPa) = 1490 K
Until the piston starts rising no work is done so the heat transfer is the change in internal energy
Qin = ΔU = m*cv*(T₂-T₁)
⇒ Qin = 0.5*3.1156*(1490 - 298) kJ = 1857 kJ
Answer:
I. 3.316 kW
II. 1.218 kW
III. 2.72
Explanation:
At state 1, the enthalpy and entropy are determined using the given data from A-13.
At P1 = 200kpa and T1 = 0,
h1 = 253.07 kJ/kg
s1 = 0.9699 kJ/kgK
At state 2, the isentropic enthalpy is determined at P2 = 1400kpa and s1 = s2 by interpolation. Thus
h2(s) = 295.95 kJ/kg
The actual enthalpy is then gotten by
h2 = h1 + [h2(s) - h1]/n
h2 = 253.07 + [295.95 - 253.07]/0.88
h2 = 253.07 + 48.73
h2 = 301.8 kJ/kg
h3 = h4 = 120.43 kJ/kg
Heating load is determined from energy balance, thus,
Q'l = m'(h1 - h4)
Q'l = 0.025(253.07 - 120.43)
Q'l = 0.025 * 132.64
Q'l = 3.316 kW
Power is determined by using
W' = m'(h2 - h1)
W'= 0.025(301.8 - 253.07)
W'= 0.025 * 48.73
W'= 1.218 kW
The Coefficient Of Performance is Q'l / W'
COP = 3.316/1.218
COP = 2.72
