Answer:
δu/δx+δu/δy = 6x-6x =0
9r^2
Explanation:
The flow is obviously two-dimensional, since the stream function depends only on the x and y coordinate. We can find the x and y velocity components by using the following relations:
u =δψ/δy = 3x^2-3y^2
v =-δψ/δx = -6xy
Now, since:
δu/δx+δu/δy = 6x-6x =0
we conclude that this flow satisfies the continuity equation for a 2D incompressible flow. Therefore, the flow is indeed a two-dimensional incompressible one.
The magnitude of velocity is given by:
|V| = u^2+v^2
=(3x^2-3y^2)^2+(-6xy)^2
=9x^4+18x^2y^2+9y^2
=(3x^2+3y^2)^2
=9r^2
where r is the distance from the origin of the coordinates, and we have used that r^2 = x^2 + y^2.
The streamline ψ = 2 is given by the following equation:
3x^2y — y^3 = 2,
which is most easily plotted by solving it for x:
x =±√2-y^3/y
Plot of the streamline is given in the graph below.
Explanation for the plot: the two x(y) functions (with minus and plus signs) given in the equation above were plotted as functions of y, after which the graph was rotated to obtain a standard coordinate diagram. The "+" and "-" parts are given in different colors, but keep in mind that these are actually "parts" of the same streamline.
Answer:
- def median(l):
- if(len(l) == 0):
- return 0
- else:
- l.sort()
- if(len(l)%2 == 0):
- index = int(len(l)/2)
- mid = (l[index-1] + l[index]) / 2
- else:
- mid = l[len(l)//2]
- return mid
-
- def mode(l):
- if(len(l)==0):
- return 0
-
- mode = max(set(l), key=l.count)
- return mode
-
- def mean(l):
- if(len(l)==0):
- return 0
- sum = 0
- for x in l:
- sum += x
- mean = sum / len(l)
- return mean
-
- lst = [5, 7, 10, 11, 12, 12, 13, 15, 25, 30, 45, 61]
- print(mean(lst))
- print(median(lst))
- print(mode(lst))
Explanation:
Firstly, we create a median function (Line 1). This function will check if the the length of list is zero and also if it is an even number. If the length is zero (empty list), it return zero (Line 2-3). If it is an even number, it will calculate the median by summing up two middle index values and divide them by two (Line 6-8). Or if the length is an odd, it will simply take the middle index value and return it as output (Line 9-10).
In mode function, after checking the length of list, we use the max function to estimate the maximum count of the item in list (Line 17) and use it as mode.
In mean function, after checking the length of list, we create a sum variable and then use a loop to add the item of list to sum (Line 23-25). After the loop, divide sum by the length of list to get the mean (Line 26).
In the main program, we test the three functions using a sample list and we shall get
20.5
12.5
12
Answer:
Newton per square meter (N/m2)
Explanation:
Required
Unit of ultimate tensile strength
Ultimate tensile strength (U) is calculated using:
The units of force is N (Newton) and the unit of Area is m^2
So, we have:
or
<em>Hence: (c) is correct</em>
Answer:
0.0280Kg/s
Explanation:
Given:
W = 1500
V2 = 300
V1 = 0
Q = 0 ( adiabatic)
T1 = 300
T2 = 20 m/s = converting to degrees we have 353°c
Let's use the energy equation
[/tex] m_• = W / (Cp(dT) + 0.5*V2^2) [/tex]
Answer:
PF= .54
Explanation:
Power Factor equals working/real power (W) over apparent power (VA). 1.0 PF is an efficient equipment. PF= 22/(120*.34)
