A random experiment consists of selecting two balls in succession from an urn containing two black balls and and one white ball.
1 answer:
You might be interested in
Answer:
- hoop stress
- longitudinal stress
- material used
all this could led to the failure of the garden hose and the tear along the length
Explanation:
For the flow of water to occur in any equipment, water has to flow from a high pressure to a low pressure. considering the pipe, water is flowing at a constant pressure of 30 psi inside the pipe which is assumed to be higher than the allowable operating pressure of the pipe. but the greatest change in pressure will occur at the end of the hose because at that point the water is trying to leave the hose into the atmosphere, therefore the great change in pressure along the length of the hose closest to the end of the hose will cause a tear there. also the other factors that might lead to the failure of the garden hose includes :
hoop stress ( which acts along the circumference of the pipe):
αh = EQUATION 1
and Longitudinal stress ( acting along the length of the pipe )
αl = EQUATION 2
where p = water pressure inside the hose
d = diameter of hose, T = thickness of hose
we can as well attribute the failure of the hose to the material used in making the hose .
assume for a thin cylindrical pipe material used to be
≥ 20
insert this value into equation 1
αh = = 60/2 = 30 psi
the allowable hoop stress was developed by the material which could have also led to the failure of the garden hose
Answer:
design angle ∅ = 4.9968 ≈ 5⁰
Explanation:
First calculate the force Fac :
Fac =
=
= 708.72 Ib
using the sine law to determine the design angle
hence ∅ =
= = 4.9968 ≈ 5⁰
Answer:
a) Mechanical efficiency ()=63.15% b) Temperature rise= 0.028ºC
Explanation:
For the item a) you have to define the mechanical power introduced (Wmec) to the system and the power transferred to the water (Pw).
The power input (electric motor) is equal to the motor power multiplied by the efficiency. Thus, .
Then, the power transferred (Pw) to the fluid is equal to the flow rate (Q) multiplied by the pressure jump . So
.
The efficiency is defined as the ratio between the output energy and the input energy. Then, the mechanical efficiency is
For the b) item you have to consider that the inefficiency goes to the fluid as heat. So it is necessary to use the equation of the heat capacity but in a "flux" way. Calling <em>H</em> to the heat transfered to the fluid, the specif heat of the water and the density of the water:
[/tex]
Finally, the temperature rise is: