Answer:
COP of heat pump=3.013
COP of cycle=1.124
Explanation
W = Q2 - Q1 ----- equation 1
W = work done
Q2 = final energy
Q1 = initial energy
A) calculate the COP of the heat pump
COP =Q2/W
from equation 1
Q2 = Q1 + W = 15 + 7.45 = 22.45 KW
therefore COP =22.45/7.45 = 3.013
B) COP when cycle is reversed
COP = Q1/W
from equation 1
Q1 + W = Q2 ------ equation 2
Q2 = 15 Btu/s = 15 * 1.055 = 15.825 KW therefore from equation 2
Q1 = 8.375 KW
COP =8.375/7.45 = 1.124
Answer:
See attachment and explanation.
Explanation:
- The following question can be solved better with the help of a MATLAB program as follows. The code is given in the attachment.
- The plot of the graph is given in attachment.
- The code covers the entire spectrum of the poly-tropic range ( 1.2 - 1.6 ) and 20 steps ( cases ) have been plotted and compared in the attached plot.
Answer:
-50.005 KJ
Explanation:
Mass flow rate = 0.147 KJ per kg
mass= 10 kg
Δh= 50 m
Δv= 15 m/s
W= 10×0.147= 1.47 KJ
Δu= -5 kJ/kg
ΔKE + ΔPE+ ΔU= Q-W
0.5×m×(30^2- 15^2)+ mgΔh+mΔu= Q-W
Q= W+ 0.5×m×(30^2- 15^2) +mgΔh+mΔu
= 1.47 +0.5×1/100×(30^2- 15^2)-9.7×50/1000-50
= 1.47 +3.375-4.8450-50
Q=-50.005 KJ
Answer:The Urban heat island temperature will be REDUCED.
Two Impacts of Rooftop gardens
1) provision of shade against Sunlight.
2) It helps to purify the air around the building.
Explanation: Rooftop gardens are gardens made on top of the roofs of buildings, it is a Green initiative aimed at helping to improve the overall Environment.
Rooftop gardens have several significant benefits which includes
Reduction of the surrounding temperatures and the Urban heat Island temperatures.
Rooftop gardens helps to shade the roof from the direct impacts of harsh weather conditions.
Generally, plants are known as air purifiers as they remove the excess Carbondioxide around the environment through photosynthesis, and they also help to release water vapor which will help to improve the humidity of the environment.
Answer:
b
Explanation:
only if there signal is turned on
