Unit Definition and 1000 Threads

Homework Statement I am trying to plot a graph of stopping voltage against frequency The given equation is eV0 = hf - w0 So i need to change it to the form of y = mx + C in order to plot this graph V0 = h*f/e - w0/e V0 = h/e * f - w0/e -- > V0 = y , m(gradient) = h/e , x= f and -w0/e = C (y...

Homework Statement If you have a ring of charge, is it valid to say lambda = Q/L, or is it lambda = dQ/dL? Homework EquationsThe Attempt at a Solution

I know that for two points, the difference between them is a line segment lets say these two points are 'a' and 'b' respectively, so b-a = "new vector represent the line" In my textbook b-a=d*t -- where 'd' is a vector along the directon of 'b-a' and t is a parameter. does 'd' actually...

Homework Statement A point source emits visible light isotropically. Its luminous flux is 0.11 lumen. Find the flux whithin the cone that has half angle of 30 degree from the light source. Homework Equations luminous flux = luminous intensity * solid anlge The Attempt at a Solution I tried...

I've been trying to solve this question all day. If somebody could point me in the right direction I would really appreciate it! (ii) A particle’s motion is described by the following position vector r(t) = 4txˆ + (10t − t)ˆy Determine the polar coordinate unit vectors ˆr and ˆθ for r. [4]...

Hi! Another Physics homework question that needs solving immediately! Thank you in advance. A computer base unit of mass 7.5 kg is dragged along a smooth desk. If the normal contact force is 23 N and the tension in the arm of the person dragging it acts at 23° to the horizontal, then what is...

Firstly, I'd be happy to be corrected if I'm not using the right wording or just plain incorrect with my approach. Is it practical to suggest that units of one measurement system could possibly represent the measurement of things not only at the macro level, but represent particles with and...

Homework Statement Suppose ##F(x, y, z, u, v) = xy^2 + yz^2 + zu^2 + uv^2 + vx^2 ## Standing at the point ##(1, 1, 1, 1, 1) ## imagine moving in a direction ##\vec w ## where ##\vec w ## is a unit vector. Find the components of a vector ##\vec u ## such that ## D_\vec u F = 0 ## Remember...

Hello guys , have a question and I can not find the answer. In what units is measured elastic limit ? Thanks A lot !

Hi. What do we mean unit SCFH AIR ? how can convert to m3/hr?

I am reading an article by Vernon Chi on quaternions and rotations in 3-space. The title of the article is as follows: I am concerned that I do not follow the proof of one of the properties of unit quaternions in Section 3.1.3 of the article. Section 3.1.3 reads as follows: In the above text...

Hello Guys, I am a mechanical engineering student and taking nuclear engineering course. Professor told me to search SWU (separative work unit). I know the general formula and the value function... But I need the derivation of that formula from entropy... Is there any document that you can...

Homework Statement https://dl.dropboxusercontent.com/u/88040310/powerhw3.png 1. Draw the reactance diagram. 2. Calculate the per unit impedances 3. If bms #1 is operating at 30 kV, find the current Assume base of 100 MVA, 300 kV on the generator side. Homework Equations P = VI s = p +jq...

Maxwell's equation is ∇×H=J + ... but the unit of H is A/m while J's unit is A/m2 as quoted from wikipedia how can it be possible?

Find in rectangular coordinates a unit vector which is: A. in the direction of E at P(2,3,-4)if $\overline{E}=(x^2+y^2+z^2)\left(\frac{xa_{x}}{\sqrt{y^2+z^3}}+\frac{ya_{y}}{\sqrt{x^2+z^2}}+\frac{za_{z}}{\sqrt{x^2+y^2}}\right)$; B. Perpendicular to the plane passing through M(1,-5,5), N(-2,4,0)...

Hello, How do we write this correctly: 1 mm or 1mm? Thanks.

I am trying to figure out what the total thermal energy emitted by completely transparent matter. It seems Planck's law can't do this because the thickness or geometry of the mass is not given, only it's surface area. The spectral radiance of a black body is given by Planck's law...

The problem: The velocity ~v (vector notation, don't know how to type) is given by: ~v = (6.0t - 4.0t^2)ˆi + 8.0ˆj + (3.0t) with |~v| in meters per second and positive t seconds. ˆi, ˆj, ˆk have their usual meanings (unit vector notation). (a) What is the acceleration ~a of the particle when...

Consider a vertical pendulum affected by gravity (See the pdf file i included). Now i can choose two different opposite directions for my unit vectors which give me different equations. \downarrow : m\ddot x = mg-kx \uparrow : m\ddot x = kx-mg Which of course makes perfect sense, changing...

hi all I have a question about unit for collision frequency. The unit is collision per second and is it same with hertz? Thanks

Homework Statement Suppose that the function ##f(z)## is analytic and that ##|f(z)| \le 1## for all ##|z| = 1##. Homework EquationsThe Attempt at a Solution I was hoping someone could verify my work. Okay, if I understand correctly, ##|f(z)| \le 1## is true for all all complex numbers ##z##...

Hello. I'm reading some accelerator physics paper showing the momentum unit for the accelerated particles as MeV/c. I'm not interested in the momentum but energy thus I really want to convert this to energy. How it is done? Simply multiplying c? if so, there must be some reason for justify...

Homework Statement Given the ellipse ##0.084x^2 − 0.079xy + 0.107y^2 = 1 ## Find the semi-major and semi-minor axes of this ellipse, and a unit vector in the direction of each axis. I have calculated the semi-major and minor axes, I am just stuck on the final part. Homework Equations this...

2m+(50s)(0.5m/s) = 2m + 25m/{s}^{2} = Not possible My teacher keeps saying this is pure piffle and shaking his head. Can someone please explain this to me?

Homework Statement Homework Equations v(x)t= -wAsin(w+o) The Attempt at a Solution -5(10)sin(0)= 0 D is this the right procedure?

I have been trying to find an ammeter that can perform a specific task and failing miserably. I would appreciate any help I can get. and as you may soon notice, I have no engineering background. I am trying to find a non-invasive method for measuring the current generated in an electrosurgical...

prove that the quotient space obtained by identifying the points on the southern hemisphere, is homeomorphic to the whole sphere.I am trying to define a homeomorphism between the quotient space and the sphere,and i need help doing it. Thank's in advance.

Homework Statement Is there a constant parrallel to the ε0 permittivity in the Gauss law in c.g.s? Homework Equations Coulomb force in m.k.s: ##F=\frac{1}{4\pi\varepsilon_0}\frac{qq'}{r^2}## Coulomb force in c.g.s: ##F=\frac{qq'}{r^2}## Gauss's law in m.k.s: ##\frac{N}{A}=\varepsilon_0 E##...

I need to convert kcal/(mol-Angstrom) to eV/Angstrom. I have force values in eV/Angstrom, which I can easily convert to Newtons. I just can't find any conversion factor anywhere on the web for kcal/(mol-Angstrom) to Newtons or eV/Angstrom! Any advice?

the unit h is referring to height or the Planck constant ze

I'm trying to find the azimuthal angle unit vector \vec{\phi} in the cartesian basis by taking the cross product of the radial and \vec{z} unit vectors. \vec{z} \times \vec{r} = <0, 0, 1> \times <sin(\theta)cos(\phi), sin(\theta)sin(\phi), cos(\theta)> = <-sin(\theta)sin(\phi)...

Homework Statement The fraction of volume unoccupied in the unit cell of the body centered cubics lattice is? Homework EquationsThe Attempt at a Solution I got the volume occupied by the atoms as (8/3)πr3. I am not sure if it is right. I just assumed that all the atoms were of same element. I...

Hi Folks, I have a function x {e^{-x}} and if i shift it one unit to the right on the x-axis we have (x-1) {e^{-(x-1)}} How do I show this mathematically? Even consider the simple case of x^2, if we shift by 1 unit to the right it becomes (x-1)^2 What is the method mathematically? Regards

Hi all, I have a general question about the unit in formula or equation. In some formula like ##F=md^2x/dt^2## or thermal radiation law ##P \propto A\cdot T^4##, if we plug in the unit for each quantity, the resulting unit of the output is the resulting algebra of the units. For example $$[F]...

What is the difference between the unit dead load and the unit weight of a material? For example, the unit weight for structural concrete is 145lb/ft^3. What would the unit dead load be? 145lb?

Hello I'm getting confused when I want to use magnetic boundary equation could you tell me how we define the unit vector(an) in this equation? for example you assume that we have two different region (A in red and B in yellow) which vector (1,2,3,4) is right for equation and which is right...

Homework Statement A sample of a hydrocarbon is combusted completely in O2(g) to produce 19.65gCO2(g), 4.023gH2O(g), and 280kJ of heat. Calculate the value of ΔH∘f per empirical-formula unit of the hydrocarbon. Homework Equations None I know of The Attempt at a Solution Previous calculations...

If a question asks for the direction of the maximum gradient of a scalar field, is it acceptable to just use del(x) as the answer or is the question asking for a unit vector? Thanks

We use ms-1 for unit of speed. But what is the physical unit for teleporting a mass to a distance L? Is it also [L]/[time]? But it seems it does not take time for teleport. I am seeking help. Thanks very much.

We use ms-1 for unit of speed. But what is the physical unit for teleporting a mass to a distance L? Is it also [L]/[time]? But it seems it does not take time for teleport. Seeking help. Thanks p.s: my reference http://www.nature.com/nature/journal/v488/n7410/full/nature11332.html

Homework Statement [/B] Sun Tyrant: 25, 28, 25, 28, 29, 24, 28, 24, 24, 28, 30, 24, 22, 27 Sun Acrid: 29, 31, 29, 26, 28, 22, 25, 29, 29, 27, 28, 23, 26, 29 Laminatekist: 25, 26, 26, 26, 26, 28, 27, 26, 25, 28, 24, 28, 27, 25 This data set shows the number of raisins in each of 14 boxes of...

I would like to reopen a discussion on assertions made by David Mermin such as: “There is no conceivable way to assign such instruction sets to the particles from one run to the next that can account for the fact that in all runs taken together, without regard to how the switches are set, the...

If one atomic mass unit is 1/12 of a C-12 atom, so 1 amu must be; 1 Amu = 1/2 ( Mass of proton + Mass of neutron + Mass of electron ) But the equation gives the answers that 1 amu is 1,6737 10^(-27) kg, which is different than the internet says I am using very sensitive values for the...

This isn't really so much of a specific example from a textbook, I just need to understand how to do this kind of integral and from that I can infer how to do all of the other problems. 1. Homework Statement The current problem I'm having trouble with is: Integral of (5u(t-1)) from T to -T...

please someone explain me the following expression for Cartesian unit vectors expressed by the cylindrical unit vectors: http://web.mit.edu/8.02t/www/materials/modules/ReviewB.pdf at page B-8 line B.2.4 i would like to know which steps led to it. thanks, Chen

Homework Statement Find convolution of x[n] (graph in attachment) and h[n] where h[n] = u[n] Homework EquationsThe Attempt at a Solution - flipped the h[n] to have h[-n] - moved to the left once (h[-1-n]) to align - multiplied h and x and it gives me all zeros Is this correct or I'm missing...

Homework Statement electric field polarization for a given antenna is expressed as: E_i = (a_x + a_y) E (r, theta, phi) The unit vector along the antenna polarization is found as u_a = 1/Sqrt(2) (a_x + a_y)2. Question Where/how is the 1/Sqrt(2) found to resolve those other 2 vectors into a...

Homework Statement During the Cold War the US and the former Soviet Union built up enormous arsenals of nuclear weapons. Although the exact amounts are not known, particularly for the USSR, the stockpile of the US arsenal alone is knowledgeably estimated to have a total destructive power of...

Homework Statement So the full problem reads: A vector F has the same magnitude and direction at all points in space. Choose the z-axis parallel to F. Then , in Cartesian coordinates, \vec{F}=F\hat{z}, where \hat{z} is the unit vector in the z direction. Express \vec{F} in spherical...

Homework Statement A and B are two unit vectors in the x-y plane. A = <cos(a), sin(a)> B = <cos(b), sin(b)> I need to derive the trig identity: sin(a-b) = sin(a) cos(b) - sin(b) cos (a) I'm told to do it using the properties of the cross product A x B Homework Equations A x B =...