Answer:
try 40
Step-by-step explanation:
3. A disc of radius a, initially at temperature zero, is placed in an environment where its boundary temperature is fixed at To(o). Use the separation of variables method to find the time-dependent temperature field T(r, 0,t). (The problem is two-dimensional.) Give the result in the form of an infinite series with coefficients expressed as definite integrals of known functions. (25 points)
The time-dependent temperature field T(r,0,t) in the disc of radius a is expressed in the form of an infinite series with coefficients expressed as definite integrals of known functions.
The solution of the two-dimensional problem at hand requires solving the heat equation in a disc with a fixed boundary temperature, using the separation of variables technique. The heat equation is given by:
\(\frac{\partial T}{\partial t}=k\left(\frac{\partial^2 T}{\partial r^2}+\frac{1}{r}\frac{\partial T}{\partial r}\right)\),
where T is the temperature, k is the thermal diffusivity, and r is the radius.
Using the separation of variables method, we assume a solution to the heat equation of the form:
\(T(r,0,t)=\sum\limits_{n=1}^\infty A_n(t) \cdot \phi_n(r)\)
where Aₙ are time-dependent coefficients and φₙ are the eigenfunctions of the Helmholtz equation, satisfying the boundary conditions
\(\phi_n(a)=0 \quad\) and \(\quad \phi_n'(a)=0.\)
These eigenfunctions are given by \(\phi_n(r)=\sin\Big(\frac{n\pi}{a}r\Big).\)
Substituting this form of T(r,0,t) into the heat equation and rearranging yields
\(\frac{dA_n}{dt}=k\frac{n^2 \pi^2}{a^2}A_n\)
which has the solution
\(A_n(t)=A_n(0)e^{\frac{n^2 \pi^2}{a^2}kt}\)
The initial condition of T(r,0,t) must also be considered. Initial temperature is zero everywhere for the given problem, hence
\(T(r,0,0) = \sum\limits_{n=1}^\infty A_n(0) \cdot \phi_n(r) = 0\)
This gives the initial conditions
\(A_n(0) \cdot \phi_n(r) = - \sum\limits_{m=1, m\neq n}^\infty A_m(0)\phi_m(r)\).
Allowing m to go to infinity, we obtain an expression for each of the A_n(0) coefficients in terms of the orthonormal basis functions:
\(A_n(0)= -\int_0^a \sum\limits_{m=1, m\neq n}^\infty A_m(0)\phi_m(r) dr\).
Now, using the boundary condition of T(a,0,t) = To(0), we obtain an expression for the Aₙ(0) coefficients in terms of definite integrals.
\(A_n(0) = \frac{1}{\phi_n(a)} \Big[\int_0^a T_0(r)dr - \int_0^a \sum\limits_{m=1, m\neq n}^\infty A_m(0)\phi_m(r) dr\Big]\)
Substituting the expression for A_n(0) back into the general solution, we get
\(T(r,0,t) = \sum\limits_{n=1}^\infty A_n(t) \cdot \phi_n(r)\)
\(= \sum\limits_{n=1}^\infty \Big[\frac{1}{\phi_n(a)} \Big(\int_0^a T_0(r)dr - \int_0^a \sum\limits_{m=1, m\neq n}^\infty A_m(0)\phi_m(r) dr\Big) \cdot e^{\frac{n^2 \pi^2}{a^2}kt}\Big] \cdot \phi_n(r)\)
Therefore, the time-dependent temperature field T(r,0,t) in the disc of radius a is expressed in the form of an infinite series with coefficients expressed as definite integrals of known functions.
To learn more about the function visit:
https://brainly.com/question/28303908.
#SPJ4
Dividing Decimals: Rounding the quotient
0.03 divided by 0.148 =
The quotient when 0.03 is divided by 0.148 after rounding it off is 0.2.
According to the question,
We have the following information:
0.03 is divided by 0.148
Now, we have the quotient as:
0.2027
Now, when rounding off the numbers we know that the digits from where we are rounding off we look at the right next to that digit and when that digit is greater than 5 then the digit should be increased by 1 and when that digit is less than 5 then the digit should be the same.
So, we will round it off by taking the underlined digit to be next to first 2:
So, the digit is 0.
Then, we have:
0.2
Hence, the quotient when 0.03 is divided by 0.148 after rounding it off is 0.2.
To know more about quotient here
https://brainly.com/question/16134410
#SPJ1
What is another name for 250/250?
Answer:
1
Step-by-step explanation:
12
11
10
9
8
4
3
-12-11-10 -9 -8 -7 -6 -5 -4 -3 -2 -1
1 2 3 4 5 6 7 8 9 10 11 12
-2
-3
-4
-5
-6
-7
-8
-9
-10
-11
-12
Answer:
You didn't say what the question was
Answer: 3
Step-by-step explanation:
if cdg ~ edf what is the value of x
Answer:
250 in out to radical change
(-3) to the sixth power in exponential form
Answer:
Step-by-step explanation:
A negative number raised to an even exponent gives a positive result so it is the same as 3 raised to 6. That is 3 x 3 x 3 x 3 x 3 x 3 = 729
The (-3) to the sixth power, (-3)⁶, is equal to 729.
To express (-3) to the sixth power in exponential form, we write it as (-3)⁶.
Now, let's calculate (-3)⁶ properly:
(-3)⁶ = (-3) * (-3) * (-3) * (-3) * (-3) * (-3)
Multiplying -3 by itself six times:
(-3) * (-3) * (-3) * (-3) * (-3) * (-3) = 729
Therefore, (-3) to the sixth power, (-3)⁶, is equal to 729.
By raising -3 to the power of 6, we obtain the result of 729.
To know more about power:
https://brainly.com/question/15149964
#SPJ6
the penguin exhibit at a zoo has a raised circular island that is surrounded by water. the diameter of the island is 20 meters 20 meters20, start text, space, m, e, t, e, r, s, end text. one penguin swims half way around the island before hopping out. how far did the penguin swim?
The penguin swims half the circumference of the circular island, which is equivalent to half the distance around the circle.
The circumference of a circle can be calculated using the formula:
C = πd,
where C is the circumference and d is the diameter of the circle.
Given that the diameter of the island is 20 meters, the radius (r) of the island is half the diameter, which is 10 meters.
Substituting the value of the radius into the formula, we have:
C = π * 10 meters = 10π meters.
To find half the circumference, we divide the total circumference by 2:
Half circumference = (10π meters) / 2 = 5π meters.
Therefore, the penguin swims a distance of 5π meters.
learn more about equivalent here
https://brainly.com/question/25197597
#SPJ11
5. Which of the following transformations maps Figure A onto Figure B?
A) Translate Figure A 3 units right, and then reflect it across the x-axis.
B) Reflect Figure A across the x-axis, and then translate it 3 units left.
C) Reflect Figure A across the y-axis, and then translate it 3 units right.
D) Translate Figure A 3 units right and 2 units down.
-7654321
2
Figure A
123456
Figure B
Answer:
A)
Step-by-step explanation:
just look at the picture.
what must have happened to figure A to turn into figure B ?
is B more to the right or to the left of A ?
well, right. isn't it obvious ?
and when you look at the coordinates of a vertex, it is 3 units to the right of A.
and if the shift to the right had not happened - the 2 figures would be a mirrored image of each other with the x-axis being the mirror.
that is why A) is the right answer.
For items 7-10, use the figure shown. Find the coordinates of the specified vertex after the given sequence of transformations.
Quadrilateral Q R S T plotted on a coordinate plane with vertices at, Q, (1, 3), R, (3, negative 3), S, (zero, negative 2), and T, (negative 2, 1).
a translation 2 units right, then a reflection across x = 0
Q' = ( , )
The coordinates of the specified vertex after the given sequence of transformations is given by;
Q' = (3, -3).
What is a translation?In Mathematics, the translation of a geometric figure to the right simply means adding a digit to the value on the x-coordinate (x-axis) of the pre-image of a function while a geometric figure that is translated up simply means adding a digit to the value on the y-coordinate (y-axis) of the pre-image or parent function.
Mathematically, a horizontal translation to the right is modeled by this mathematical expression g(x) = f(x + N) while a vertical translation to the positive y-direction (upward) is modeled by this mathematical expression g(x) = f(x) + N.
Where:
N represents an integer.g(x) and f(x) represent a function.By translating the coordinate Q (1, 3) two (2) units to the right, we have the following:
Coordinate Q (1, 3) → Coordinate Q' (1 + 2, 3) = Q (3, 3)
In Mathematics, a reflection across the x-axis would maintain the same x-coordinate while the sign of the y-coordinate would change from positive to negative. Therefore, a reflection over the x-axis is given by this transformation rule:
(x, y) → (x, -y)
Coordinate Q' (3, 3) → (3, -3).
Read more on reflection here: brainly.com/question/10260342
#SPJ1
John and Mary are building towers out of lego bricks. John used fewer than 18 bricks for his
tower. Mary used twice as many bricks as John. What is the greatest number of bricks Mary
could have used?
Answer:
34 bricks is the greatest amount Mary could have used
Step-by-step explanation:
24 PLUS 18 IJIEWJFQFHQR
Answer:
37
Step-by-step explanation:
Answer:
24+18 is 42.
Step-by-step explanation:
1
24
+18
____
42
Please help! (Also show work)
Tutorials :D
The five-number summary is:
Minimum: 9
First Quartile: 16.5
Median: 25.5
Third Quartile: 39
Maximum: 51
3. Range = 42
4. Interquartile range = 22.5
How to Find the Five-number Summary of a Data?Given the data for the lengths as, 36, 15, 9, 22, 36, 14, 42, 45, 51, 29, 18, 20, to find the five-number summary of the data set, we would follow the steps below:
1. The numbers in ordered from the smallest to the largest would be:
9, 14, 15, 18, 20, 22, 29, 36, 36, 42, 45, 51
2. The five-number summary for the lengths in minutes would be:
Minimum value: this is the smallest lengths, which is 9First Quartile (Q1): this is the middle of the first half of the data set of the lengths in minutes, which is 16.5.Median: the median is the center of the data distribution which is 25.5.Third Quartile: this is the middle of the second half of the data set of the lengths in minutes, which is 39.Maximum: this is the largest length in minutes, which is, 51.3. Range of the data = max - min = 51 - 9 = 42
4. The interquartile range for the data set = Q3 - Q1 = 39 - 16.5
Interquartile range for the data set = 22.5
Learn more about the five-number summary on:
https://brainly.com/question/24809873
#SPJ1
ACTIVITY 2
Here are some equations that all have the same solution. Explain how you know
that each equation has the same solution as the previous equation.
x = -6
X-3= -9
-9 = x-3
900 = -100(x - 3)
900 = (x-3) (-100)
900 = -100x + 300
Answer:
Step-by-step explanation:
x = -6
subtract 3 from both sides: x-3 = -9
reflexive identity: x-3 = -9, so -9 = x-3
multiply both sides by -100: 900 = -100(x-3)
commutative law for multiplication: -100(x-3) = (x-3)(-100)
distributive rule: (x-3)(-100) = -100x + 300
How to Find the Factors of 13
The components of a number are the numbers that divide evenly into it. To find the factors of 13, divide 13 by each number from 1 to 13 and check whether or not the result is an integer. 13 is made up of two factors: 1 and 13.
What is division?Division is one of the four fundamental arithmetic operations that allows integers to be connected to produce new numbers. Addition, subtraction, and multiplication are the other operations. Division is the process of dividing a given amount into equal pieces in mathematics. For example, a group of 20 people can be divided into four groups of five people each, or five groups of four people each, and so on. Splitting anything involves dividing it into two or more equal halves, such as an area, class, category, group, or division. To divide something simply is to cut it in half and give it to a group.
Here,
A number's components are the numbers that split equally into it. To determine the factors of 13, divide 13 by each number from 1 to 13 and see if the result is an integer or not. 13 has two factors: 1 and 13.
To know more about division,
https://brainly.com/question/28598725
#SPJ4
Can someone please help me out
Step-by-step explanation:
\( \sqrt{ - 81} = 9i \\ \sqrt{ - 11} = i \sqrt{11} \\ \sqrt{ - 20} = i \sqrt{20} \)
The value of Hector's house has increased by 5%.
His house is now valued at £609 000
Work out the value of the house before the increase.
Answer:
$580000
Step-by-step explanation:
To find decrease we simply reverse the operations of increase
increase is x x 1.05 = 609000
x = 609000 / 1.05 = 580000 initial value
x= $580000
proof
580000 x 1.05 = 609000 new value
find the value of "a" and "b" for which the limit exists both as x approaches 1 and as x approaches 2:
Answer:
a = 4
b = -2
Step-by-step explanation:
If the given function is continuous at x = 1
\(\lim_{x \to 1^{-}} f(x)=(x+1)\)
\(=2\)
\(\lim_{x \to 1^{+}} f(x)=ax+b\)
\(=a+b\)
\(\lim_{x \to 1} f(x)=ax+b\)
\(=a+b\)
And for the continuity of the function at x = 1,
\(\lim_{x \to 1^{-}} f(x)=\lim_{x \to 1^{+}} f(x)=\lim_{x \to 1} f(x)\)
Therefore, (a + b) = 2 -------(1)
If the function 'f' is continuous at x = 2,
\(\lim_{x \to 2^{-}} f(x)=ax+b\)
\(=2a+b\)
\(\lim_{x \to 2^{+}} f(x)=3x\)
\(=6\)
\(\lim_{x \to 2} f(x)=3x\)
\(=6\)
Therefore, \(\lim_{x \to 2^{-}} f(x)=\lim_{x \to 2^{+}} f(x)=\lim_{x \to 2} f(x)\)
2a + b = 6 -----(2)
Subtract equation (1) from (2),
(2a + b) - (a + b) = 6 - 2
a = 4
From equation (1),
4 + b = 2
b = -2
Owen loves reading and started counting the total number of books reads this year. He adds up the total at the end of each month and his list as follows: {4, 7, 10, 13) Which equation represents the number of books he is reading?
Select one:
1) y = x+ 3
2) y = 3x +1
3) y = 4x
4) y = 3x
Answer: its answer 3, most likely
Step-by-step explanation: i remember this question
you have completed the next step of the six-step process and have determined that you require one package of c4 for a single charge. how many packages will you need to complete the mission? calculate the total number of packages of explosives, and then submit your response in numerals.
You would need a total of 10 packages of C4 to complete the mission.
To answer your question, we need to calculate the total number of packages of explosives required.
Since you've already determined that you need one package of C4 for a single charge, we can use that information to calculate the total number of packages needed for the entire mission.
Let's say that you need to perform a total of 10 charges to complete the mission. Since you need one package of C4 for each charge, the total number of packages required would be 10 times the number of packages needed for a single charge, which is one.
To know more about total here
https://brainly.com/question/14286201
#SPJ4
Find the missing angle measure.
Can someone tell me the answer to this please
Answer:
sum of all angles of a triangle= 180°
Let angle A be x,
then 63°+90°+x=180°
x=17°
they want me to round the result to the correct number of significant figures.
The first part:
\(24.9\times1.99=49.551\)Since the first number is 1 decimal place and second number is 2 decimals, we will round to 1 decimal.
Thus,
49.551 = 49.6
Next part of the problem becomes:
\(49.6\div106.19\)The calculation provides the answer: 0.4670...
The first number has 3 significant figures, that's the limit because next number has 5 significant figures. So, we round off our answer to 3 significant figures (3 decimal place, in this case)
Thus, the answer is:
0.467
Consider the given matrix B= row1(2 2 0) ; row2(1 0
1); row3(0 1 1). Find the det(B) and use it to determine whether or
not B is invertible, and if so, find B^-1 ( hint: use the matrix
equation BX= I)
To find the determinant of matrix B, we can use the formula for a 3x3 matrix: det(B) = (2 * (0 * 1 - 1 * 1)) - (2 * (1 * 1 - 0 * 1)) + (0 * (1 * 1 - 0 * 1))
Simplifying this expression, we get:
det(B) = (2 * (-1)) - (2 * (1)) + (0 * (1))
det(B) = -2 - 2 + 0
det(B) = -4
The determinant of matrix B is -4.
Since the determinant is non-zero, B is invertible.
To find the inverse of B, we can use the matrix equation B * X = I, where X is the inverse of B and I is the identity matrix.
B * X = I
Using the given values of B, we have:
|2 2 0| * |x y z| = |1 0 0|
|1 0 1| |a b c| |0 1 0|
|0 1 1| |p q r| |0 0 1|
Solving this system of equations, we can find the values of x, y, z, a, b, c, p, q, and r, which will give us the inverse matrix B^-1.
Learn more about matrix here
https://brainly.com/question/94574
#SPJ11
The kite shown has a width of 24 inches and a total height of 42 inches. What is the total area of the kite without the tail? Show your work for full
credit.
Answer:
504 in²
Step-by-step explanation:
The area of a kite is given by :
(a * b) / 2
Where a and b are the width and height of the kite :
Width = 24 inches ; height = 42 inches
Hence,
Area of kite = (24 * 42) / 2
Area of kite = 24 * 21
Area of kite = 504 in²
The new bookcase for your future dorm room has the dimensions of 24 in wide by 12 in deep by 36 in tall. If one average textbook has the dimensions of 8.5 in wide by 11 in long by 1.5 in tall, how many books could you fit on your bookshelf with no shelving?
Answer:
About 73.93 books. Round that to 73 books, because you can't place 93% of a book.
Step-by-step explanation:
You first calculate to dimensions of the bookcase, then you calculate the dimensions of the books. As a result, divide the calculation of the bookshelf by the calculation of the books, and you should have your answer.
An instructor is preparing a report showing mid-semester grades and notes that the mean, median, and mode are all exactly 76.00. What can she conclude
The instructor can conclude that the class performed around the average and that the distribution of grades is likely to be symmetrical. This can also imply that there is no skewness or bias in the data. Answer more than 100 words:When an instructor notes that the mean, median, and mode are all exactly 76.00, it can be inferred that the distribution of grades in the class is roughly symmetrical. This indicates that there are nearly equal numbers of students above and below the average grade.
The mean, median, and mode are three measures of central tendency that are used to summarize the distribution of a dataset. The mean is calculated by adding all the values in the dataset and dividing by the number of observations, while the median is the middle value when the dataset is ordered from smallest to largest. The mode is the value that occurs most frequently in the dataset. When all three measures of central tendency are equal, as in this case, it means that the dataset is roughly symmetrical and there is no skewness or bias. This can also indicate that the dataset is normally distributed, which means that it follows a bell-shaped curve.The instructor can conclude that the class performed around the average, as the mean, median, and mode are all 76.00.
However, it is important to note that this does not give any information about the spread of the dataset. In other words, the instructor cannot tell from this information alone whether the grades were tightly clustered around the average or widely dispersed. For this reason, it may be useful to calculate additional measures of spread, such as the range or standard deviation, to get a better understanding of the distribution.
The instructor can conclude that the class performed around the average and that the distribution of grades is likely to be symmetrical, with no skewness or bias. However, it is important to remember that this information alone does not provide any insight into the spread of the dataset. Additional measures of spread would need to be calculated to determine the degree of variability in the grades.
To know more about mean, median, and mode visit:
brainly.com/question/21035124
#SPJ11
A number, c, rounded to 1 d.p. is 47.3
Another number, d, rounded to 1 d.p. is 4.6
What are the lower and upper bounds of c- d?
The lower and upper bounds of c- d are 42.0 and 43.0 respectively.
What is termed as the rounding off?Rounding off merely refers to an estimate. Rounding off is the process of estimating this same actual number to a nearby number.Examine this same unit place digit:If indeed the unit place digit is a little less than 5, keep a tens place digit unchanged and replace it with 0.Whereas if unit place is 5 or greater, replace the tens digit with its successor and place 0 just at unit place.For the given question;
A number, c, rounded to 1 decimal place is 47.3
Another number, d, rounded to 1 decimal place is 4.6
c- d = 47.3 - 4.6
c- d = 42.7
Lower bound = 42.0
Upper bound = 43.0.
Thus, the lower and upper bounds of c- d are 42.0 and 43.0 respectively.
To know more about the rounding off, here
https://brainly.com/question/27207159
#SPJ10
Find out the silk density in g/cc if the specific gravity of the fiber is given as 1.32. Provide your answer with two decimal positions and no unit.
The silk density in g/cc if the specific gravity of the fiber is given as 1.32 is given as 1.32 g/cc.
Density is the mass of a material substance per unit volume. d = M/V, where d is density, M is mass, and V is volume, is the formula for density. Grams per cubic centimetre are a typical unit of measurement for density.
For instance, whereas Earth has a density of 5.51 grammes per cubic centimetre, water has a density of 1 grammes per cubic centimetre. Another way to state density is in kilogrammes per cubic metre (in metre-kilogram-second or SI units). For instance, air weighs 1.2 pounds per cubic metre. In textbooks and manuals, the densities of typical solids, liquids, and gases are stated.
As we know that ,
Specific gravity = Density of object / density of water
1.32 = silk density / 1 g/cc
[Density of water is 1 g/cc]
Silk density = 1.32 x 1 g/cc
Silk density = 1.32 g/cc.
Learn more about Density:
https://brainly.com/question/12654738
#SPJ4
Corresponding Angles are congruent.
Which angle corresponds with <4?
4546
47 48
<[?]
41 42
43/44
Answer:
Angle 8
Step-by-step explanation:
consider the following image
Answer:
∠8Step-by-step explanation:
The angles in matching corners are called Corresponding Angles.
The angle that corresponds with ∠4 is ∠8 as both of them are on the bottom right corner.
Long division synthetic remainder theorem and factor theorem
\((4n^3 - 18n + 21 - 8n^2) ÷ (2n - 6)\)
answer step by step:
hope this helps
What theorem is being applied if two triangles of one triangle are congruent to two angles of another triangle and the triangles are similar?
Triangle congurent theorem is being applied if two triangles of one triangle are congruent to two angles of another triangle and the triangles are similar.
Angle-Side-Angle (ASA) theorem states that if two triangles are considered congruent, then the two corresponding angles equal to each other will include a corresponding side that is equal to each other.
By applying the Side Angle Side Postulate (SAS), you can also be sure your two triangles are congruent. Here, instead of picking two angles, we pick a side and its corresponding side on two triangles.
The SAS Postulate says that triangles are congruent if any pair of corresponding sides and their included angle are congruent.
Perhaps the easiest of the three postulates, Side Side Side Postulate (SSS) says triangles are congruent if three sides of one triangle are congruent to the corresponding sides of the other triangle.
Learn more about Triangle congurent theorem here ;
https://brainly.com/question/20104844
#SPJ4