Answer:
Yes
Explanation:
Yes it is true that COP of heat pump always greater than 1.But the COP of refrigeration can be greater or less than 1.
We know that
COP of heat pump= 1 + COP of refrigeration
It is clear that COP can not be negative .So from the above expression we can say that COP of heat pump is always greater than one.
Answer:
critical stress = 595 MPa
Explanation:
given data
fracture toughness = 74.6 MPa-
crack length = 10 mm
f = 1
solution
we know crack length = 10 mm
and crack length = 2a as given in figure attach
so 2a = 10
a = 5 mm
and now we get here with the help of plane strain condition , critical stress is express as
critical stress =
......................1
put here value and we get
critical stress =
critical stress = 595 MPa
so here stress is change by plane strain condition because when plate become thinner than condition change by plane strain to plain stress.
plain stress condition occur in thin body where stress through thickness not vary by the thinner section.
Answer:
water sample have more water content
Explanation:
given data
soil 1 is saturated with water
unit weight of water = 1 g/cm³
soil 2 is saturated with alcohol
unit weight of alcohol = 0.8 g/cm³
solution
we get here water content that is express as
water content =
....................1
here soil is full saturated so
is 100% in both case
so put here value for water
water content = 100 % × 1
water content = 1 g
and
now we get for alcohol that is
water content = 100 % × 0.8
water content = 0.8 g
so here water sample have more water content
Answer:
heat transfer rate is -15.71 kW
Explanation:
given data
Initial pressure = 4 bar
Final pressure = 12 bar
volumetric flow rate = 4 m³ / min
work input to the compressor = 60 kJ per kg
solution
we use here super hated table for 4 bar and 20 degree temperature and 12 bar and 80 degree is
h1 = 262.96 kJ/kg
v1 = 0.05397 m³/kg
h2 = 310.24 kJ/kg
and here mass balance equation will be
m1 = m2
and mass flow equation is express as
m1 =
.......................1
m1 =
m1 = 1.2353 kg/s
and here energy balance equation is express as
0 = Qcv - Wcv + m × [ ( h1-h2) +
+ g (z1-z2) ] ....................2
so here Qcv will be
Qcv = m × [
] ......................3
put here value and we get
Qcv = 1.2353 × [ {-60}+ (310.24-262.96) ]
Qcv = -15.7130 kW
so here heat transfer rate is -15.71 kW