Volume Definition and 1000 Threads

This is the general equation for the packing parameter to find out what shape the lipids arrange into: And this is what we have been given in class: http://i.imgur.com/iGsbXHi.jpg I'm struggling with the surfactant tail volume, v term. I understand the a is the optimal surface area...

Homework Statement An iron casting weighs 300 N in air and 200 N in water. What is the volume of cavities in the casting, if the density of iron is 7800 kg/m3 ? Homework Equations d = m/V Fg = mg The Attempt at a Solution I was not sure in the slightest of how to solve this problem. So I...

Homework Statement there is an expandable container with 1m3 of hydrogen and 1/2 m3of oxygen at stp. the gas is ignited.what is th final volume if there is no heàt lost and the pressure outside the container is 1atm? assume complete combustion Homework Equations other than the ideal gas...

Homework Statement Find the volume of the solid. Under the paraboloid z = x^2 + y^2 and above the region bounded by y = x^2 and x = y^2 Well, those curves only intersects in the xy-plane at (0,0) and (1,1), and in the first Quadrant, and in that first Quadrant y = sqrt(x), and over that...

Homework Statement 2. Homework Equations n/a The Attempt at a Solution [/B]1) Whenever I need to find the volume between two surfaces, the integrand is simply the difference (subtraction) of the two equations? In the solution guide above, it is clear that they subtracted the two...

Use the method of cylindrical shells to find the volume of the solid obtained by rotating the region bounded by the given curves about the x axis. $x=1+{y}^{2}$, $x=0$, $y-1$, $y=2$ https://www.physicsforums.com/attachments/4237 The answer is $\frac{21\pi}{2}$ but I couldn't get it using...

Suppose someone gives you a rectangular sheet of length a and width b (so b ≤ a). You make a topless box by cutting out a square with length x out of each corner and folding up the sides. How should you cut the sheet so as to maximize the volume of your box?

Its given in my textbook that equivalence of gas = (volume of gas) / (Volume of 1 eq. gas at NTP) How do i calculate volume occupied by 1 equivalent of gas? Example: What would be the volume occupied by 1 eq. of CO2 (Its given 11.2l in my book) Is there a formula for this?

Homework Statement In a particular region of the Earth's atmosphere, the electric field above the Earth's surface has been measured to be 148 N/C downward at an altitude of 260 m and 165 N/C downward at an altitude of 410 m. Calculate the volume charge density of the atmosphere, assuming it to...

Hello everyone, I have a discrete class D project that I need help with but since I'm not an analog guy I got a problem. So far I got everything set up and the discrete class D works perfectly. But only at maximum of 6 volts otherwise the Transistor M3 gets really hot and burned, how do I solve...

Hello everyone, I just need some help understanding some thermodynamics. So I have 0.25 kg of helium which is compressed from an initial state in a polytropic process with n = 1.3. So its given the change in volume and the initial pressure. I need to find the change in internal energy. I am...

This is probably an elementary question, but I stumbled upon it while thinking about total differentials. One of their many applications is calculating the error in a volume, for example, given uncertainties in its dimensions. I'm not in the mood to tackle a 3D problem, so let's revert to a 2D...

Hi all, I need help finding a formula to find the volume of a solid that has a fixed width and depth but 4 different heights. To see what I mean, please take a look at a sketch I drew below. Thanks.

Find the density

Homework Statement Just want to check that I've used the correct method for this thermodynamics question I've been set. Any clarification would be greatly appreciated. So I have 0.5kg of gas held in a rigid container of volume 0.25m^3 at a temperature of 20°C. 20kJ of heat energy is required...

Hi evryone, the system i am working on, is composed of two relatied non-linear equations that I discretised using finite volume method with fully implicit scheme, the difficulty is that the two unknonw appear in both equations and i don't know how to solve it. Any propositions? Thank you.

hey guys. bellow is an upside down cone frustum with the dimensions given bellow where the green R is the radius of the larger circle and the blue r is the radius of the smaller circle and the red h to be the height of the object knowing that volume of this shape is calculated as...

Homework Statement Find the centre of mass of solid cone. Homework Equations $$y_{cm}=\frac{1}{M}\int_0^Hydm$$ The Attempt at a Solution First I took thin disks. I got the answer when I assumed its thickness to be dy but then dysecθ would be more accurate if half angle of cone is θ since...

Homework Statement (3 i) Using \nabla . \mathbf{F} = \frac{\partial \mathbf{F_{\rho}}}{\partial \rho} + \frac{\mathbf{F_{\rho}}}{\rho} + \frac{1}{\rho} \frac{\partial \mathbf{F_{\phi}}}{\partial \phi} + \frac{\partial \mathbf{F_{z}}}{\partial z} calculate the divergence of the vector field...

A solid is generated by revolving the region bounded by y=(1/2)x2 and y= 2 about the y-axis. So what I did is set up my integral V= 2pi (integral sign from 0 to 2) x(1/2)(x)2 dx When I solve i get 4pi, and then I have to find the radius of the hole which has one fourth of the volume. So the...

Homework Statement Find the volume V of the region that lies inside the quarter cylinder 0 ≤ r ≤ 1, 0 ≤ θ ⇐ 1/2 π and between the planes x+y+z=4 and z=0, where (r, θ, z) are cylindrical polar coordinates. Homework Equations integral dV = integral r drdθdz The Attempt at a Solution I...

Homework Statement Dear Mentors and PF helpers, I can do part (a) and (b) but don't really know how to do (c) and (d). Can somebody teach me how to go about solving it. Homework Equations Volume of cone: $$\frac{1}{3}πr^2h$$ Volume of cylinder: $$πr^2h$$ Volume of sphere...

Hey, I am new in this forum and looking forward to learn physics which I hate :) My first question concerns possibility, in theory. Say, there is a water tank. Let us say that we made a nanometer hole. The tank is full. Then, we put even more water through that hole. But the hole has something...

Homework Statement The region bounded by the graphs of the curves y=4√x , y=0, x=5, x=12 is revolved about the x-axis. a) Find the religion lateral surface area of the generated volume. b) Find the total surface area of the generated volume, including both ends. Homework EquationsThe Attempt at...

Homework Statement Problem - If the volume of the carry-on luggage is 2000 cubic inches, determine two possibilities for its depth. Where necessary, round to the nearest tenth of an inch Homework Equations V(x) = x(x+10)(30-2x) Volume function is given above The Attempt at a Solution I...

Homework Statement Find the volume generated by x=0 x=π y=2sin(x/2) y=sin(x) using the shell method. Homework Equations x=2arcsin(y/2) x=arcsin(y) The Attempt at a Solution So to setup my integral I got the following values, Outer Radius=(2-arcsin(y)) Inner Radius=(2-2arcsin(y/2)) I'm...

Homework Statement 5 lbs of nitroglycerin detonates. What is the total volume of the gases produced? Homework Equations PV=nRT The Attempt at a Solution I used the balance chemical equation of the decomposition of nitroglycerin and used stoichiometry to find the number of moles of nitrogen...

I need a website or a program that I can write an equation then find volume in Disk or washer or cylindrical and draw it ? it should be Free

Question: The height of the given vessel is h,and the width of the given vessel is b (as given in the diagram). The density of the liquid is r.Find the force exerted by the liquid on the slant wall. Relevant formulae : P = F/A F = Vdg An attempt at the solution...

At STP, a mole of hydrogen gas would take up 22.4 L. If that hydrogen gas was ionized and stripped of 100% of the electrons, would the remaining protons have a larger volume than 22.4 L? I'm not sure because on one hand, taking away the electrons leaves each proton with much less volume, but on...

Homework Statement What equation is needed to calculate the height of a spherical cap with a fixed volume and radius? Homework Equations V=πh/6 (3a^2 + h^2) Where V = volume, h is cap height, a is cap radius The Attempt at a Solution I have tried to separate the h out and got as far as...

Hey! :o A liquid flows through a flat surface with uniform vector velocity $\overrightarrow{v}$. Let $\overrightarrow{n}$ an unit vector perpendicular to the plane. Show that $\overrightarrow{v} \cdot \overrightarrow{n}$ is the volume of the liquid that passes through the unit surface of...

Homework Statement [/B] (a) Find the proper distance (b) Find the proper area (c) Find the proper volume (d) Find the four-volume Homework EquationsThe Attempt at a Solution Part (a) Letting ##d\theta = dt = d\phi = 0##: \Delta s = \int_0^R \left( 1-Ar^2 \right) dr = R \left(1 -...

I am working on a take home with a group of students and we all got different answers for this problem... can anyone look over it and tell me where I am going wrong?? Let me know if any of my work is confusing...

I understand why entropy (a state function) is very useful in chemistry. Since most chemistry systems are at constant pressure, ##\Delta H=Q_v## from the derivation below: ##H=U+PV## ##dH=dU+dPV+PdV## ##dU=\delta Q-\delta W## ## dU=\delta Q-PdV## ## dH=\delta Q+dPV## ##dPV=0## ## dH=\delta...

For a van der Waals gas, there are London dispersion forces causing the gas particles to be attracted to each other while the law of excluded volume provides repulsive forces. How do each of these characteristics effect the pressure, volume, and temperature of the gas? I assumed that for the...

The question is... So of course I rearrange my ellipse formula to get y=\pm\sqrt{1-\frac{{x}^{2}}{4}} Then I calculate my radius as x-(-2)=r \implies x+2=r I know the formula for finding volume with the Shell Method is V=\int_{a}^{b}2\pi x\cdot f(x) \,dx To make it easier I decide to just...

Homework Statement A question in my chemistry 151 lab book: A student measures the volume of water displaced by the same metal sample as 5.4 mL, 5.8 mL, and 5.5 mL for his three determinations. Determine the median volume. Homework Equations Unknown or N/A The Attempt at a Solution How do...

Homework Statement A tank for scuba diving is designed to contain 50 standard cubic feet of air when filled to a pressure of 3,000 pounds per square inch (gage) at an ambient temperature of 80 F. Calculate the interior volume of the tank. A standard cubic foot occupies one cubic foot at T=15...

Hi can anyone please suggest me how to find out the rate at which gas in LPG cylinder reduce.Initially before use gas cylinder will be full as the consumer start using the gas it starts reducing how do i calculate how much is left out and the rate at which it is getting reduced ,And also if a...

Homework Statement Find the volume of the solid bounded by the cylinder y^2+z^2=9 and the planes x=0, y=0, z=0, and 2x+y=2. Homework Equations None. The Attempt at a Solution This is double integral problem. I know how to find the double integral but I don't know how to set it up. How do I...

Homework Statement Find volume when the area rotates around a line. Homework Equations x=y^2 x=1-y^2 about x = 3 The Attempt at a Solution Could someone please check my formula for Area? I have pi[ (3-(y^2))^2 - (2-(y^2))^2 ] which gives me the integral pi[5y-(2/3)y^3]. I think...

Homework Statement How do you find the volume of the solid obtained by rotating the region bounded by the given curves about the specified lines? I keep getting a negative number and I"m becoming so frustrated! 11pi/30 is the answer in the textbook. Thank you so very much in advance...

Can a singularity expand in volume?

Imaginary numbers enable one to envision a lot of ideas. But what kind of numbers/algebras would enable us to work with imaginary volumes? Volumes, by definition, always seem to be positive, since any cubes are. What kind of numbers would give/allow a more complex picture?

Homework Statement Of the objects below, which is the most dense? A. an object with a volume of 13 dm3 and a mass of 1.29 × 103 g B. an object with a volume of 0.00212 m3 and a mass of 4.22 × 104 mg C. an object with a volume of 3.91 × 10-24 nm3 and a mass of 7.93 × 10-1 ng D. an object with...

Hallo, Working on building a cloud chamber based on thermoelectric coolers rather than dry ice or other "consumable" cooling methods, and having some difficulty working out some of the numbers. Say I have a volume of air at room temperature, for arguments sake 1600cm³, and I want to cool this...

Homework Statement I've seen this problem appear in more than one textbook almost without any changes. It goes like this: Assume the entropy ##S## depends on the volume ##\bar{\Omega}## inside the energy shell: ##S(\bar{\Omega})=f(\bar{\Omega})##. Show that from the additivity of ##S## and the...

Homework Statement Hi guys, My first post here, I hope someone can help me out with a quick fluid mechanics problem. I'm looking to calculate the pressure increase inside a closed tube full of water when the tube is crushed and therefore its volume reduced. The tube is filled completely...

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...