Balance Definition and 461 Threads

Homework Statement Quote from the question source: Homework Equations None given, but maybe: Torque = lever arm x force The Attempt at a Solution I drew a diagram which you can see here: http://i.minus.com/ibzw9bF4vAnaJ.png (The weight differences are probably very exaggerated.) But I am...

All problem info, and my work is done in the attached pdf. Basically, I'm not sure that I have done it correctly.

finding the "energy balance" of a hydroelectric power generator I proposed a new hydroelectric energy idea to somebody and they asked me for a "energy balance". I know nothing about physics or anything relevant to calculating something like this. If somebody asked you for the energy balance of...

http://resources.scienceworld.ca/pdf/forces/Balance_Hammer.jpg How do I explain this in terms of centre of mass? And what's the definition of centre of mass in this context?

This was a question from one of my tutes earlier in the semester, and now that I'm revising for an exam I can't seem to remember how to do it. If anyone can help that would be great! Sulfuric acid is a major bulk chemical used in a wide variety of industries. After sulfur is oxidized to...

Homework Statement Balance Cl2+NaOH -> NaCl + NaClO3 + H2O

I need to do an energy balance on a heat exchanger where an aziotropic mixture of 90% methanol and 10% water at 21°C is being heated to 261°C. The heat source is high pressure saturated steam at 31 bar and it is assumed that the steam leaves as condensate at the same pressure (31bar)...

How in a series circuit do the components know how much of the "electricity" to use? How does this happen? Why doesn't the first lamp in a series use all the volts? How does it know if there are any other lamps in the circuit? Any help would be greatly appreciated. :)

i met a brilliant scientist about a year ago he invented one very very important item that saved millions of lives little is known about space from an outsiders perspective atleast is yet scientists have to work with truths it seems like a delicate balance to find truths about space...

If resting potential is negative, then K+ ions shouldn't be passively exiting the cell. It doesn't make sense for a male that is attracted to females to leave a club full of females and go outside where there are lots of males. There are females to be had!

Homework Statement The PDE: ∂n/∂t + G∂n/∂L=0 The initial condition: n(0,L)=ns The boundary condition: n(t,0)=B/G The parameter B and G above are dependent upon process conditions and change at each time. They can be calculated with adequate experimental data. Homework Equations...

When I am reading the paper in fluid mechanics, I found a paragraph and two equations: "Since the fluid is considered Newtonian and incompress- ible of density ρ and constant viscosity μ, the dimensionless mass and momentum balance equations are:" \nabla \cdot \mathbf{v} = 0...

If I was interested in determining how to balance the rate of reinvestment of profits back into the original investment (to add to its compounding potential) while still growing the profit return on the investment. How would I go about calculating something like that ?

Homework Statement A 900 kg car goes up along an inclined road by 30 degrees characterized by an acceleration of 0.25 m/s^2. If friction coefficient is 0.5, find the magnitude of the force that moves the car. Solution: F = 12285.6 N Homework Equations The Attempt at a Solution...

It is told, that all homework-like threads should be posted there. So, here I go. Imagine such a situation: there is a vertical rod and a cylinder, with the hole diameter sightly larger than the diameter of rod. There is also a second rod, attached to the cylinder perpendicularly. There is a...

Imagine such a situation: there is a vertical rod and a cylinder, with the hole diameter sightly larger than the diameter of rod. There is also a second rod, attached to the cylinder perpendicularly. There is a friction between the main rod and the cylinder. It is known, that if we put a...

Hi! I am trying to build a stand with a boom arm for my acting classes and I need to find the weight required to balance it. The problem is that it looks like I was more like a swan when I was swimming in the physics lessons ... no a lot of drops stayed on my plumage ... :) Help...

I looked for hours and hours and I haven't been able to find any video or link [there's one REALLY bad video on youtube] and I REALLY need to know how a current balance works because that specific chapter that I'm studying on electromagnetism has questions mostly coming up with the current...

Is the amount of oxygen in the air always the same?if yes,how?or if not, how not?

I'm working on an ac circuit, and we were told to use nodal analysis. Furthermore, we are asked to show a power balance between the sources and the power dissipated in the resistors, along with a reactive power balance between the sources and the inductors and capacitors. I have this formula...

In the context of power systems, what does it mean for a load to be unbalanced? Or for that matter, balanced?

how do you determine the mass of a liquid using an electronic balance ?:S Anyone knows how ?

Homework Statement 01"{ 5. (12)A balance beam device comprised of a 200 cm long beam of unobtainium (no mass) ] \]and a fulcrum located in the middle of the beam is balanced straight and level. At the right side of the beam system a mass of 30 kg is attached and at the other end of the...

Hello, I am after a little help on an applicaition, I need to calculate the force require to hold a pivoted arm in a position using a pneumatic ram. Basically the arms C of G is 740mm up the arm, and the arm weights 100kg. Roughly 1000N working at an offset of 147mm. The arm is 16 degrees...

Homework Statement This is a single displacement reaction aluminum + hydrochloric acid --> Homework Equations The Attempt at a Solution Since I know its single displacement, and I know that aluminum can't trade places with chlorine because one is a metal and one is a non-metal...

Homework Statement If conducting a Coulomb Balance experiment, and a question asks to estimate the total excess charge on a sphere with a conducting surface charged to 2,000,000V potential. Is there a specific equation I should be using to estimate this? Thank you. P.S. why are...

Homework Statement A gymnast with mass m1 = 48 kg is on a balance beam that sits on (but is not attached to) two supports. The beam has a mass m2 = 121 kg and length L = 5 m. Each support is 1/3 of the way from each end. Initially the gymnast stands at the left end of the beam. 1)What is the...

I do online schooling or I'd just ask a teacher anywho I need to find the calculated mass of a slug by difference, I'm using centigram balance to calculate everything. This is what I know so far: Snug w/ beaker: 52.42g Snug: 2.42 Beaker: 50g I don't know if I should divide or subtract them.

I have to deliver this problem resolved in 4 hours, I didn't think it was going to be so hard... Homework Statement A man of mass M is on the top of a balance with a very high damping coefficient. In a given instant he throws a ball of mass m vertically, catching it again later. a)...

Hi guys, I'm currently doing an assignment which seems to be beyond my knowledge and would like to ask for some helps. There are 2 questions I am currently stuck on: 1] A natural gas analyzes CH4, 80.0 percent and N2, 20.0 percent. It is burned under a boiler and most of the CO2 is scrubbed...

So like say you have (AlK(SO4)2•12H2O) And then how does the reaction go? Is it like (AlK(SO4)2•12H2O) -> AlOH + H2SO4 or something like this? Was also wondering how like (NaCH3COO) would work with H2O as well... same for this (Cu(NO3)2•2.5H2O) These are acid-base, and I am pretty new to...

hello everyone, In a hydraulic cylinder high amount of load is lifted by applying lower loads in smaller diameter side.. for example, if the diameters of two cylinders is 2cm and 4 cm and i applied a force of 10 N on the 2cm cylinder for 4m downwards. so now the 4cm diameter cylinder could...

Confused about a simple thing... For a common balance, since both arms have equal weight, what causes the pole to choose a horizontal position? Shouldnt it be stable in any other position as the torque around the centre is zero for any other position too?

the question asks me to balance the following equation C2H3NO + H2O ---> C2H8N2O + 2CO2 i attempted to balance it 2C2H3NO + H2O ---> C2H8N2O + 2CO2 i can't get all the oxygens to be equal, if someone can show me how to do this last step, id appreciate it also can one use...

Hi Guys, I was hoping someone would be able to help me with this integration. It's been killing me haha. I've got this energy balance equation: mgh = 0.5m(v^2) + 0.5I(w^2) + T(theta) Basically, It's a gravitational potential energy that is converted to a velocity of a falling object...

I have argued with others on the Talk Polywell forum about the Nuclear Binding Energy per Nucleon vs the Total Nuclear Binding Energy per Nucleus graphs (which is the NBE/Nucleon * the atomic mass number). Despite referenced statements that, while the total binding energy increases continuously...

I just took my balance in my 401K program out of all stocks, bonds, and corporate stock funds and put the into FIXED. I never thought I would see this day happen, but what I see (not happening) in Washington in addressing the debt limit gives me cause for concern. IMHO, it is better to...

For PF members that are within driving distance, please contact me if you want to save up to 40% over the factory-store prices on these shoes for your kids and yourself. My wife would like to enjoy her vacation, but if I asked her, she would be happy to accompany you to the sale and apply her...

when a can of coke placed in a sensitive balance is opened what happens to the reading? the answer of this question is given first increases and decreases. can anyone explain this?

Homework Statement You are to design, build and test a method to accurately measure the mass of an object. You cannot directly weigh the object but must use experimental data to determine your result. You cannot build any type of spring balance or beam balance. You are to determine your method...

I bought some fruits from the market yesterday and after returning home, I found that some fruits were not weighed properly. In my country (India), they use traditional beam balances. I ordered for 0.5 kg berries and found that they were only 360g on an electronic balance. Does anyone here know...

I was trying to figure out the following - assume you have an old fashioned balance scale, with two pans hanging from a lever with a fulcrum in the middle of the lever. On one side you have a weight of X, and on the other side you have a weight Y. If Y is big enough, that side of the scale...

A spring balance cannot be used to measure the weight of anything under the conditions of a space shuttle. Is there any way you might use a spring balance to compare the 'heaviness' of twin babies born on the shuttle? Discuss. I don't know how you'd use a spring balance in the shuttle.. Any...

https://www.physicsforums.com/attachments/33615 I have problem with these two questions, can you give me a hint and help to understand it, I do understand problem 7-3 but i have problem with applying the equastion, I don't understand to 7-2 but i knw we have to have an addition term for the...

I am going over some thermodynamics right now and I am looking at the energy balance equation which is dE/dt = mdot*j(in) - mdot*j(out) + Qdot + Wdot(external) I understand this means that the change in energy with respect to time equals the sum of the mass energy that goes into a system, minus...

I'm looking at a surface at an angle. Light reflected to me is polarised (Fresnel), does this mean light emitted to me from the surface is also polarised? I've been told that ocean emission is polarised (when looking at an angle) because of Kirchoff's law of radiative balance (emissivity =...

If an ordinary balance with two equal weights is displaced slightly from its equilibrium position then it regains its original position. Why? There is no unbalanced torque at any position. So why should it regain its position? I am totally confused on this one. Can anyone help...

Homework Statement Describe how you would prepare exactly 250 mL of .180 M K2S2O8 solution for use. Assume that you have a supply of solid K2S2O8, deionized water, a balance, and a volumetric flask. Also, how many grams of K2S2O8 would you need? Homework Equations The Attempt at a...

http://www.ted.com/talks/nigel_marsh_how_to_make_work_life_balance_work.html?utm_source=newsletter_weekly_2011-02-08&utm_campaign=newsletter_weekly&utm_medium=email" Nigel has a dry sense of humor, even though a few lines I have heard in other contexts before, IMHO, worth watching...

Homework Statement 10 g Fe and x ml H2SO4 forms y gFeSO4*7H2O Write a balanced chemical equation for the reaction, and determine the coeffisients y and x. The H2SO4 is 1 M. Homework Equations n=V*c n=m/Fm The Attempt at a Solution First thing I was trying to set up the chemical...