In very early human history, complex sanitation systems were not needed because settlements were usually very small, like the vi
llage shown below.
However, as cities became larger and population densities increased, one major advancement was the development of _______, which helped to channel wastewaters away from human populations more effectively than in the past.
A.
fountains
B.
water towers
C.
sewer systems
D.
dams
However, as cities became larger and population densities increased, one major advancement was the development of _______, which helped to channel wastewaters away from human populations more effectively than in the past.
A.
fountains
B.
water towers
C.
sewer systems
D.
dams
2 answers:
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Answer:
input power of the geothermal motor will be 0.4166 hP
Explanation:
We have given shaft output = 0.25 hP
hP is known as horse power which is unit of measuring the power of motor
Efficiency of motor is given as efficiency = 60 % = 0.6
We have to fond the heat supply by the fan motor Q
We know that efficiency of any motor is the ratio of shaft power and input power
So
So
So input power of the geothermal motor will be 0.4166 hP