Answer:
Correct option a) True.
Explanation:
It is true since the Vickers hardness value refers to the force applied in a 136 ° diamond tip penetrator divided by the surface of the groove produced in the material, the lower the impression made on this greater the value will be end of the Vickers measurement and greater its hardness.
The equation to determine the Vickers hardness value will be:
Hv= ((1.854 × P)/(d²)) (kg/mm²)
Therefore a value of 220 Vickers refers to a harder material than another value of 180 Vickers.
Answer: (B) 100
Explanation:
Given that;
Pstatic = 20 psig , hz = 160ft, hf = 20ft
Now total head will be;
T.h = hz + hf
T.h= 160 + 20
T.h = 180ft
Minimum pressure = Psatic + egh
we know that specific weight of water is 62.4 (lb/ft3)
so
P.min = (20 bf/in² ) + (62.4 b/ft³ × 180 fr
P.min = (20 bf/in² ) + ( 62.4 × 180 × 1 ft²/144 in²)
P.min = 20 + 78
P.min = 98 lbf/in²
Therefore the minimum pressure rating (psi) of the piping system is most nearly B) 100
Answer:
Explanation:
From the information given;
The velocity of the wind blow V = 7 m/s
The diameter of the blades (d) = 80 m
Percentage of the overall efficiency 
The density of air 
Then, we can use the concept of the kinetic energy of the wind blowing to estimate the mechanic energy of air per unit mass by using the formula:

here;
m = 
= 
= 43982.29 kg/s
∴




The actual electric power is:



D
Step by step explanation