In object-oriented computer programming, SOLID is a mnemonic acronym for five design principles intended to make software designs more understandable, flexible, and maintainable. The principles are a subset of many principles promoted by American software engineer and instructor Robert C. Martin, first introduced in his 2000 paper Design Principles and Design Patterns.The SOLID concepts are
The Single-responsibility principle: "There should never be more than one reason for a class to change." In other words, every class should have only one responsibility.
The Open–closed principle: "Software entities ... should be open for extension, but closed for modification."
The Liskov substitution principle: "Functions that use pointers or references to base classes must be able to use objects of derived classes without knowing it". See also design by contract.
The Interface segregation principle: "Many client-specific interfaces are better than one general-purpose interface."
The Dependency inversion principle: "Depend upon abstractions, [not] concretions."The SOLID acronym was introduced later, around 2004, by Michael Feathers.Although the SOLID principles apply to any object-oriented design, they can also form a core philosophy for methodologies such as agile development or adaptive software development.
Usually, we only talk about the band near Fermi surface, but we know that atom could have infinite levels, so, for a solid, does it have infinite levels too? So, if we only talk about the levels near Fermi surface, are the eigenwavefunctions complete?
Homework Statement
The exercise asks many questions about the following E(k) diagram, but I'm more interested in understanding some basic things about it, from which I'm sure i'll be able to find the answers I'm requested.
1) What do the bands actually correspond to? Is the lowest band...
Homework Statement
Homework Equations
m:mass of solid cylinder
T: tension in string
w:angular velocity
The Attempt at a Solution
m(g-a)=T
mg-ma=T
a=v^2/r=w^2r
now what?
Hello guys!
I have to solve a problem about crystal symmetry, but I am very lost, so I wonder if anyone could guide me.
The problem is the following:
Using semiclassical transport theory the conductivity tensor can be defined as:
σ(k)=e^2·t·v_a(k)·v_b(k)
Where e is the electron charge, t...
Homework Statement
Find the acceleration of a uniform solid sphere (of mass ##m## and radius ##R##) rolling without slipping down an incline at angle ##\alpha## using the Lagrangian method.
Homework Equations
Euler-Lagrange equation which says, $$\frac{\partial\mathcal{L}}{\partial...
Homework Statement
Find volume of the solid that lies above the cone Φ = π/3 and below the sphere ρ = 4cosΦ
Homework EquationsThe Attempt at a Solution
Obviously this is a triple integral. My book tells me that 0 ≤ρ≤ 4cosΦ
but this makes no sense to me.
From the problem, it lies ABOVE the...
I'm working on a project at university to calculate the magnetocaloric effect of dysprosium. This will be done using a new technique designed at the university of which its not necessary to go into detail about. In short, the Dy is placed in a solenoid, through which a current runs, the current...
Homework Statement
A solid is generated by revolving region bounded by y=(1/2)x^2 and y=12 about the y axis. A hole centered along the axis of revolution is drilled through this solid so that 1/4 of the volume is removed. find the diameter of the hole.
Homework Equations
y=(1/12)x^2 y = 12...
Hello I'm asking if the resonate frequency of a solid object say a rock. Can be transmitted/guided to change the natural frequency of an object say a rock with a different frequency. And I hope this is a proper question.
I was working at the observatory and uh someone came in with a question about landing in Jupiter- right away my brain was like no, it’s a gas giant and there’s too much pressure for a probe to make it to the solid surface, but I’ve also been trying to think of it in terms of the force applied by...
A solid sphere has surface charge density, Rho (r)
Rho(r) = k 1 ( 0 < r < a)
k2 x ( a < r < R)
2) Find the electric field in all region i.e 1) r < a and 2) a < r < R and 3 ) R <
The attempted solution and the question with the diagram is attached below
Could the answer be verified...
If water vapor is pulled inwards and cooled at a fast enough rate could if be frozen back into a solid form? i understand that they would have to be froze together as soon as contact is made but if this is possible what would the temperature have to be? And could this be the only thing that can...
Homework Statement
A solid sphere with radius R=12 m has charge Q=3 nC distributed uniformly throughout its volume.
(a) Calculate the potential difference between a location at infinity and a location on the sphere’s surface.
(b) Calculate the potential difference between a location on the...
Homework Statement
Instead of using a ballistic pendulum, a bullet with velocity u is fired at a stationary solid ball resting on a surface. If the bullet deflects at an angle of 30◦ to its original path and the ball is nine times more massive than the bullet, what is the velocity of the ball...
Homework Statement
Homework EquationsThe Attempt at a Solution
total kinetic energy of a rigid body = rotational kinetic energy of the body around its center of mass + translational kinetic energy of center of mass
For solid cylinder, total kinetic energy = ## \frac { [I = \frac 1 2...
$\tiny{M2215b.08}$
Find the volume of the solid
\begin{align*}\displaystyle y&=\sin (x^2)\\ 0&\le x \le \frac{\pi}{2}\\
\end{align*}
about the y-axis
ok this looks like a cylindrical Shell solution
So I set it up like this,,,,, hopefully
$\begin{align*}\displaystyle
V&=\int_0^12\pi...
Homework Statement
If 0.025 g of Fe(OH)3 is added to 3.84 L of water, what mass will dissolve? Ksp is 2.8E-39.
Homework Equations
Ksp = [x][x]
n= m/M
The Attempt at a Solution
I believe in this question that the starting mass is deemed irrelevant (although now i am starting to believe that is...
Homework Statement
A solid sphere of mass m=2.5 kg is rolling at v=5.3 m/s. Calculate the transitional kinetic energy, rotational kinetic energy, and the ratio of the two (Rotational/ Transitional).
Homework Equations
[/B]
Inertia of solid sphere = 2/5 mR^2 (where R is the radius and m is the...
$\textsf{Find the volume of the solid generated by revolving the region
about y-axis.Given the boundares of }\\$
\begin{align*} \displaystyle
y&=4x-x^2\\
y&=x\\
\end{align*}
Ok, I presume since this is rotated around the y-axis that we have to rewrite the equations in terms of y
$y=-(x^2-4x)$...
Managed to get through a Ph.D. in nuclear physics without covering nuclear matter calculations (or I just don't recall it). My question is does nuclear matter have any shear strength, or is it like an ideal gas? What little I see of elementary calculations it's like a fermi gas so one would...
I'm finishing my degree in Engineering Physics (really just physics). Without a doubt my favorite area of physics is solid state physics. While I love computational and theoretical work, I don't think making a career out of it is as easy as it is in the experimental or engineering side of it. So...
$\tiny{t6.1.1}$
$\text{The solid lies between planes perpendiaular to the}$
$\text{$x$-axis at $x=0$ and $x = 4$.}$
$\text{The cross-scctions perpendicular to the axis on the interval
$0 \le x \le 4$}$
$\text{are squrares whose diagonals run for the parabola $\displaystyle f_a(x)=-\sqrt{x}$
to...
Hello,
I have a tennis racquet that has a certain weight distribution that makes it play very well. Due to quality control issues from the manufacturer my second racquet of same make and model has a very different weight profile, making matching difficult.
I'd like to determine the weight...
I would like to understand this a bit better, so I am looking for a reference to refer to and not necessarily an explanation in a reply.
I have a non-porous membrane of a compressible material wrapped around a solid body. I then draw out the air between the membrane and the solid body. I want...
Homework Statement
A solid B occupies the region of space above ##z=0## and between the spheres ##x^2 + y^2 + z^2 = 16## and ##x^2+y^2+(z-1^2) = 1##. The density of B is equal to the distance from its base, which is ##z = 0##. The mass of the solid B is ##\frac{188\pi}{3}##. Find the...
Find the centroid.
Sliced Solid Cylinder
bounded by $x^2+y^2=196$,$z=0$,$y+z=14$
so $r=14$
and $r\sin\theta +z=14$
so $z=14-\sin\theta$
$\displaystyle m=\iiint_\limits{D}{}^{} Rv = \int_{0}^{24} \int_{0}^{14} \int_{0}^{14-r\sin\theta}$...
Consider a simple circuit consisting of a battery and a parallel plate capacitor .During the process of charging of capacitors, we come to learn that half of the work done by the battery is stored in the form of potential energy and half of it is lost as heat or electromagnetic radiation...
Hello,
I would like to ask you for hints to proof this:
\int^4 pi \omega \omega \,d\omega =%fraction{4}{3} \pi
where omega is vector.
Do you have any hints for me? (Not seeing for solution, just hints).
It has been a long time since I have worked with this and I need help just starting out.
The problem involves the density of a liquid, the density of a solid, and the height where the solid will be released in the liquid, gravitational force, and the time it takes to reach the top of the...
Compute the volume of the solid bounded by the planes; $x=7, z=y-2, z=-2y-2, z=0, \mbox{ and } z=2$
Another source said the triple should be but Ii thought it should be $dx\,dy\,dz$
$$I = \displaystyle \int_0^7 \int_0^2 \int_{-\frac{z}{2} - 1}^{z+2} dy\,dz\,dx = 63$$
Hopefully this is the...
In an Elastic Collision in free space with no gravity or friction of two solid balls of radius r1 and r2 I need to calculate the momentum and kinetic energy of the induced spin with angular velocity w1 and w2 to solve for the Conservation of Momentum and Kinetic Energy.
Spin
Angular Velocity
w1...
Hi initially I am aware that large deformation in solid mechanics requires non linear strain theory in the lieu of infinitesmall strain theory. But I wonder that if we can approximate large deformation of material using infinitesmall strain of small elements employing and summing linear strains...
Hi! So I just breezed through a summer Calc II course (took E&M and Modern Physics last semester) and will be approaching Solid State Physics and Calc III this coming semester together. I've taken my school's upper division Linear Algebra course and passed before last semester and continue to do...
Actually those to subjects are in our syllabus now! Please suggest me some books which will be easy to understand and somewhere maintain my academic syllabus too !
I know that Quark-gluon plasma is the hotter state of matter that we know.
Soo is solid the coldest state of matter ?
If there is no so sorry for my stupid brain!
I googled a lot on proof of Gauss theorem and nearly every other proof (on web and so on books) state that solid angle of closed surface is 4pi but I can't find the proof of this nowhere !
I tried setting up the integral but don't know how to proceed furthur :
Ω=∫(cosθ/r^2)*dA
Also The one...
Hello Everybody!
Concept of Solid Angle was pretty much straight forward until they were on surface patches were taken into account which were visualized as base of cone.
I am having difficult when 3d Objects like Sphere/Cylinder .
We can very easily calculate the respective area and plugin the...
i work on phononic crystals and i want to find solids with diffrent sound velocities and mass density in diffrent temprature
i can just find BST
but i need more matherials
please help me my friends
best regards
Homework Statement
A solid sphere of radius 16cm and mass 10kg starts from rest and rolls without slipping a distance of 9m down a house roof that is inclined at 43 degrees.
What is the angular speed about its center as it leaves the house roof?
The height of the outside wall of the house is...
I need a book that explains the physics of pn-junction diodes. Really any reference that can help me characterize or model a diode slightly better than the ideal case.
Hello Guys! This is my first post so bear with me. I am currently studying the basics of electrostatics using the textbook "Introduction to electrodynamics 3 edt. - David J. Griffiths". My problem comes when i try to solve problem 2.21.
Find the potential V inside and outside a uniformly...
Homework Statement
Find the volume of the region bounded by the curves y=3x-2, y=6-x, and the x-axis when the region is rotated around the y-axis.
Homework Equations
Volume using cylindrical shells: 2π∫r(x)h(x)dx
The Attempt at a Solution
I graphed the curves and then found the x-intercept...
I was passing time by Googling the properties of the sun (temperature, mass, etc) and got to wondering what lies at the center of stars. I found out its plasma under roughly 340 billion atmospheres of pressure.
I realize Boyles law may not be strictly meant for plasmas, but using it I...
Hi,
I'm a newbie at Comsol and want ask for guide how to fill something with fluid and make sphere rotate. My goal in creating system where one sphere contains second. Second sphere rotates on its axis. Volume between is filled with fluid.
I understand how to create spheres, but couldn't...
When dealing with a bar (fixed on one end), if it is hollow for a certain length from the edge and then turns solid up until the fixed point, can the condition of static equilibrium be used to find the reaction torque, just like you would of a bar with 2 different diameters.
(Assuming all this...
Hi, I am trying to work out how much each dimension of a solid (for instance an annular disc) made out of steel changes assuming that the solid is heated uniformly and is not constrained at any of its boundaries. Am I right in saying that, the linear expansion equation L = L_0 (1+ α ΔT) can be...
So i was going through derivations of moments of inertia of objects. For objects like the disk and rod, i was able to assume a relationship between mass and volume and integrate From there like
$$ \frac{d_m}{m} = \frac{dl}{l} \\ d_m = \frac{dl*m}{l} \\ \int_{0}^{L}r^2\frac{dl*m}{l} \\...
I'm trying to build a fanless computer case for a small electronic device. I'm trying to figure out what type of heat-sink material I should use. I have a solid copper rod about 3cm in length with a radius of .05cm.
I've determined and calculated the density, specific heat, thermal...
Homework Statement
There is three things P, Q, R. The density of P is 2000 kg/m3, Q is 1000 kg/m3, R is 2500 kg/m3. If all of them are put into the water having density 1000 kg/m3, the correct position of the things are shown by following picture ...
[PLAIN]http://
Homework Equations
When ρ...
Homework Statement
To calculate moment of inertia of a solid sphere of uniform density[/B]Homework Equations
$$ I = \int r^2 dm$$
The attempt at a solution
I consider an elemental disk of small thickness ##d\theta##
##dm = \frac{M}{4/3 \pi R^3}*\pi R^2\cos^2\theta* Rd\theta##...