In geometry, a square is a regular quadrilateral, which means that it has four equal sides and four equal angles (90-degree angles, or 100-gradian angles or right angles). It can also be defined as a rectangle in which two adjacent sides have equal length. A square with vertices ABCD would be denoted
Homework Statement
If I measure a sound intensity of 1.0 at distance R from its source, what intensity would I measure at distance 3R in a free, unbounded space? What is the difference in decibels?
Homework Equations
I know that the equation for this is 10 (log R2/R1)
The Attempt at a...
Homework Statement
If I measure a sound intensity of 1.0 at distance R from its source, what intensity would I measure at distance 3R in a free, unbounded space? What is the difference in decibels?
&
If I measure a sound pressure of 1.0 at distance R from its source, what pressure would I...
Homework Statement
Let m be the number of numbers fromantic the set {1,2,3,...,2014} which can be expressed as difference of squares of two non negative integers. The sum of the digits of m is ...
Homework EquationsThe Attempt at a Solution
I got a solution from a magazine but I didn't under...
I need to make a steel beam ( or aluminum) of square tube ( box beam) 10 feet long with a balance point 2 feet from one end. The short end will have 60 lbs on it and the long end will have 30 lbs. how thick of a wall will the square tube need to be to hold the static load?
If you ever need a 4-by-4 Magic Square,
here's an easy way to construct one.
Draw a 4-by-4 grid
and consider the cells on the two diagonals.
$\quad\begin{array}{|c|c|c|c|} \hline
* &&& *\\ \hline
& * & * & \\ \hline
& * & * & \\ \hline
* &&& * \\
\hline \end{array}$Starting at the...
show that for x,y positive integers satisfying $3x^2+x= 4y^2+y$ each of x-y , 3x+3y+ 1 and 4x + 4y + 1 are squares. ( above equation has atleast one solution x= 30 and y = 26)
Anyone noticed this paper: Square Root of Inverse Metric: The Geometry Background of Unified Theory?
Authors: De-Sheng Li, arXiv:1412.2578 ?
The author tries to construct the square root of the inverse metric, based on a product of a fermion field and a framefield. Somehow the Standard model...
Hi,
I have a question that came into my mind while solving some problems. If I have a constant times an expression in a square root like ##4\sqrt{16}## I can square the constant and push it into the square root: ##4\sqrt{16}=\sqrt{4^2 16} = 16##. But what if the constant outside of the square...
This challenge has been provided by @Joffan
A magic square has rows, columns and diagonals summing to the same number. For a 3x3 magic square there are 8 such sums.
Given a set of 9 distinct integers which has at least 8 subsets of 3 all with a common sum, is it always possible to make a magic...
Homework Statement
The problem states, "Find the electric field a distance z above the center of a square loop (sides of length a) carrying a uniform line charge λ. " The hint says to use the result of example 2.1.
Example 2.1 is a similar problem, but instead of a square loop you are asked...
Homework Statement
A two dimensional solid has two electrons per unit cell and has a Bravais lattice with primitive vectors ##\vec a = \ell \hat x## and ##\vec b = \ell \hat y##. The crystal potential is weak and the solid behaves like a free electron metal.
a)In a reciprocal space diagram...
I was going through a p and c problem where I had to find the number of non congruent RECTANGLES.
Answer includes number of squares as well.
SHOULD SQUARE BE TAKEN AS A RECTANGLE?
Hello,
i'm having trouble evaluating my gamma factor for my special relativity homework, because I need to compute 1 minus a very small number (8.57*10^-13). My calculator treats this value as simply 1, as does Mathematica. Although I don't know much about it, and maybe there's a way to force...
Hi, I have a simple problem.
A Lambertian emitter has the shape of a square planar surface, with area Ae=4mm2,
total power P=1mW, and is located in yz plane.
Another square planar surface, with area Ad=6mm2, is located in the
xy plane, at a distance d=10cm to the Ae, and is tilted 20 Degrees...
[Note from mentor: this thread originated in a non-homework forum, therefore it doesn't use the standard homework template]
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This exercise pops up in the Cavendish Quantum Mechanics Primer (M. Warner and A. Cheung) but I can't seem to figure it out. So...
Homework Statement
let z' = (a,b), find z in C such that z^2 = z'
Homework EquationsThe Attempt at a Solution
let z = (x,y) then z^2 = (x^2-y^2, 2xy)
since z^2 = z', we have,
(x^2-y^2, 2xy) = (a,b)
comparing real and imaginary components we have;
x^2-y^2 = a,
2xy = b.
Now, this...
Homework Statement
3 point charges, q1=+2E-9[Coulomb] are placed at the corners of a square of 0.2[m] edge. what is the potential at the center.
Homework Equations
The potential of a point charge at distance r: $$V[Volt]=K\frac{q}{r}$$
##K=\frac{1}{4\pi\varepsilon_0}=9\times 10^9##
The...
Homework Statement
Evaluate following series:
\sum_{n=1}^\infty \frac{1}{(4n^2-9)^2}
by finding the Fourier series for the 2\pi-periodic function
f(x) =
\begin{cases}
sin(3x/2) & 0<x<\pi \\
0 & otherwise
\end{cases}
Homework Equations
a_n = \frac{1}{\pi}\int_{-\pi}^{\pi}...
Hello,
I am trying to work out a mean field theory for an antiferromagnetic Ising model on a square lattice. The Hamiltonian is:
## H = + J \sum_{<i,j>} s_{i} s_{j} - B \sum_{i} s_{i} ##
## J > 0 ##
I'm running into issues trying to use
## <s_{i}> = m ##
together with the self-consistency...
Hello,
I'm enrolled in College in the civil engineering program and am looking for guidance with calculating strength of steel square tubing.
We are making a project that has parameters.
1- Must be made of steel
2- 4"x6"x36" is maximum OD of section.
3- 14 lbs is maximum weight
4- the load...
X is a 4-digit perfect square all of whose decimal digits are less than seven. Increasing each digit by three we obtain a perfect square again. Find X.
Homework Statement
I need to find the area of the square in the following figure:
Homework Equations
Basic Trig relations.
The Attempt at a Solution
I aimed to find the length of BC, but first I had to find the unknowns of the right triangle CDE, which are EC=5m, <DCE=36.86ْ , <DEC=53.13ْ ...
Homework Statement
Hi there! I have a data set of r (independent variable) and E (electric field strength) (dependent variable). The question asks for a non graphical method to show if there is an inverse square law relationship between the two data sets.
--
My attempt:
I picked the equation...
Hello,
My question is, there is a concept of contour integration. Which is choosing a circular contour space sort of, and integrating along that.
How do you do contour integration?
Secondly, there is something going around called integrating along a square. I tried searching only, a lot...
Homework Statement
So image we have a square. And the center of mass is, well in the center.
If I choose the pivot to be the bottom left corner, would the distance used to calculate torque be from the bottom left to the center or to the middle on the same axis? I have a picture since it's kind...
Homework Statement
[/B]
What is the energy of an STM tunneling electron in the following state? This "quantum square" model can be seen as a "particle in a 2-D box" problem.
<Refer to the picture below>
The protrusions are Fe atoms and the surface is Cu(111).
Given that the radius of an Fe atom...
Homework Statement
Find the critical points for the function g(x, y, z) = x3+xy2+x2+y2+3z2.
Homework EquationsThe Attempt at a Solution
I've come up with the following 3 equations (derivatives set so that they are equal to 0)
(1) 3x2+y2+2x=0
(2) 2xy+2y=0
(3) 6z=0
From (3),
z=0
From (2)...
I would like to know in the following equation (attached) how can I incorporate BER for BPSK? is BER the same as Rc?
The equation is relation between SNR and sigma square.
Can anyone tell me why for example the speed of light is squared in "E=mc^2" ?
Also what does square root mean and why is it in certain equations like for example time dilation?
What happens if you exclude the square root and the y^x in a equation?
I am still studying high school physics, but...
Dear everyone,
I have a question about a property of square root.
$${\frac{1}{x}\sqrt{x^2}}$$$\implies$ $\sqrt{\frac{x^2}{x^2}}$=$\left| 1 \right|$
Is that property of a square root? Since
$$\sqrt{x^2}$$= $\left| x \right|$.
Homework Statement
The wording of the question is throwing me off. It is a standard inf. pot. well problem and we are given the initial position of the particle to be in the left fourth of the box,
\Psi(x,0)=\sqrt{\frac{4}{a}}
We are asked to a) write the expansion of the wave function in...
I have a constant 100 uA square wave DC 10Hz signal that needs to have a pulse width of 50ms. I was reading up on using an electronic timer relay (recycle type) or a solid state relay controlled via PWM. I need some help choosing which route to take, or if there are better/easier ways to...
Let \mathbb{Q}(\sqrt{2},\sqrt{3}) be the field generated by elements of the form a+b\sqrt{2}+c\sqrt{3}, where a,b,c\in\mathbb{Q}. Prove that \mathbb{Q}(\sqrt{2},\sqrt{3}) is a vector space of dimension 4 over \mathbb{Q}. Find a basis for \mathbb{Q}(\sqrt{2},\sqrt{3}).
I suspect the basis is...
Homework Statement
the expected frequency for the age of (21-30, 31-36, more than or equal to 37) for operation is less than 5 , so combination of these numbers are required for the expected frequency to be more than or equal to 5 .
my question is which numbers should i combine?
would my ans...
Homework Statement
Determine the minimum mean square error for the joint PMF. You will need to evaluate ##E_{X, Y}[(Y - 14/11\cdot X - 1/11)^2]##.
Homework EquationsThe Attempt at a Solution
The answer is ##\frac{3}{22}##, but when I work it out, I get ##\frac{203}{484}##. From my values, I...
Homework Statement
4 charges of +5µC, +3µC, -4µC and +2µC form the 4 points of a square of side length 2m. Calculate the field strength and potential at the centre of the square.
Homework Equations
F=1/4πhttp://upload.wikimedia.org/math/d/3/c/d3c305fc416b971cd6d284564e51bf85.png0 X Q1Q2/r2
E=...
Homework Statement
Consider a particle of mass m in the ground state of a potential well of width 2 a and depth.
the particle was in the ground state of the potential well with V0 < Vcritical, which means the well is a narrow one.
At t = 0 the bottom of the potential well is shifted down to Vo'...
Homework Statement
i have problem of finding the degree f freedom for this question. the ans for v is 3 , but my ans is v=n-1 , where n = 6 , so my v=5...
Homework EquationsThe Attempt at a Solution
Does there always exist primes in between square of two consecutive prime i.e Pn-1 and Pn
where Pn-1 and Pn are consecutive prime.
That is, in other words, does all the odd places between Pn-1 and Pn, are not divided, by primes less than Pn or by all primes upto Pn-1.I can only check randomly...
I have:
sq rt 2 +sq rt 2 over 2 , sq rt 5 + sq rt 5 over 2
I got (sq rt 4 over 2, and 0) = 1, 0
but the answer is actually (sq rt 2, 0)
so is my answer still wrong?
I have to find this:
$$\lim_{{x}\to{3}}\frac {\sqrt{6x - 14} - \sqrt { x+1}}{x-3}$$
So I do this:
$$\lim_{{x}\to{3}}\frac {\sqrt{6x - 14} - \sqrt { x+1}}{x-3} * \frac{\sqrt{6x + 14} + \sqrt{x+1}}{\sqrt{6x + 14} + \sqrt{x+1}}$$
The top part is easy since
$$(\sqrt{a} - \sqrt{b})(\sqrt{a} +...
Homework Statement
These are the Points.
X values: 0, 1.98, 3.96, 5.94, 7.92, 9.9
Y values: 1.98, 7.13, 9.08, 11.04, 12.57, 14.51
I need to find the original equation and the linear equation. I can't seem to find the line for square root graphs.
2. The attempt at a solution
I know it's a...
I need to find the domain of this function.$$h(x) = 1 / \sqrt[4]{x^2 - 5x}$$
So, I understand that I need to set
$$x^2 -5x > 0$$
from that I get
$$ x(x-5) > 0$$
and
$$ x > 5$$
However, the answer in the textbook is given:
$$ ( \infty, 0) \cup (5, \infty)$$
Which mean that the graph has a...
The full title of this post is "Close Packing of Spheres in Regular Tetrahedral vs. Square Pyramidal Container"
I'm not sure where this post belongs, but Greg Bernhardt suggested I just post it where I thought best, and he would find a place for it. So here goes:
In 1611, Johannes Kepler...
How does this work? (Also, I am very math illiterate and do not understand even the most basic terms, if you could kindly speak as you would to a child I would GREATLY appreciate it.)
sq rt sign over 13^2 - 12^2 (over both of it together)
Now the answer is 5, because
(13)(13) - (12)(12)...
I have a table with several quantities in it, and one of them is \sqrt{T} (T is tension)
I have values for this table, and want to put the units next to the values.
Something seems off to me about doing this, I guess because they're not integers.
Is it correct to say the units are kg1/2m1/2s-1...