Drop Definition and 876 Threads

Drop chance probability http://www.wow.com/2010/01/13/drop-chance-probability/ For some reason, the explanation provided in that document is not clear to me. Could anyone offer a different explanation?

I'm having trouble understanding expansion valves. Gas leaving a diffuser increases its pressure as the cross-section increases (i.e as the gas expands), like in a compressor. We convert kinetic energy in potential energy. That I understand. But in a expansion valve, pressure drops as the...

At what speed (flow/volume for that matter) does air leave an outlet when you know it holds x bars in the pipe? (It goes from x to zero (or athmospheric) -- you know the pressure difference) I assume you can neglect relative roughness, resistance, and so on as the pressure drop is over...

Hi, I want to know how high the flow rate trough a pipe is (outlet), but I only now the pressure difference (0.7MPa or 7 bar), and the diameter of the pipe. At what speed (or for that matter volume) does air leave a pipe when the pressure difference is 7 bar, and the diameter is 25.4mm...

Just curious: is the voltage drop across a load an expression of how much energy that device uses? If it is, what is the difference between voltage drop and power? Power is also used to determine the energy usage of a device, right? These aren't very important questions. I've just been...

Fluid Problems :( 1. Water is running out of a faucet, falling straight down, with an initial speed of 0.500 m/s. At what distance below the faucet is the radius of the stream reduced to one-half its value at the faucet? I tried doing this by using Bernoullis equation and replacing r with...

I have a number of difficult questions regarding this topic! 1. How to find the coeffients of the Liquid Drop model? I have a table of atoms with their masses, and total binding energies. Do I just fit the curve of the B/A vs A to get the coefficients? 2. In a Liquid Drop model, what...

Please see here: http://www.youtube.com/watch?v=n5bsQ_YDYCI&feature=player_embedded# First - wow. Second - I'm not sure I understand the mathematician's explanation. Why would there be a thin layer of air to begin with? Is this correct? Is there a different explanation for this...

The egg drop rules are that the container must be less than 1600 cm cubed in volume, wiht no dimension greater than 25 cm and a maximum mass of 1 kg. The eggs must be able to be easily removed after the drop from 2.5 meters. Parachutes may not be used and the device must be in one piece. Three...

Homework Statement Dear all, I am trying to find find out the shape of a drop on a flat surface. The requirement is the constant volume of the drop. Any help is greatly appreciated! Homework Equations The Attempt at a Solution I know that for the solution I must find out the...

I want to have an easier semester and I'm thinking about dropping either Globalization or Philosophy and Social Ethics. Which of these classes is usually harder? I know this may vary by professor and the university but in general which of these subjects is more difficult? Based off the...

Oil drop weighs 5.8 x 10^(-15)N. It is suspended in a uniform field produced by a pf of 363V between 2 parallel plates 6cm apart. 1. Calculate charge on drop. 2. How many excess electrons does it carry? My question is, why are the electrons excess? The answer is 6, which is basically the...

Homework Statement My physics teacher is making us do an egg drop after only being in school for two weeks. We can only use up to four 8.5" x 11" sheets of regular computer paper and as much tape as we want. The tape cannot be used as more than a form of attachment. Meaning that the tape...

Homework Statement In Fig. 28-5a calculate the potential difference across R2, assuming = 14 V, R1 = 6.0 , R2 = 3.0 , and R3 = 2.0. (image isn't working online, but it's a simple circuit- all the resistors are in series) Homework Equations V = IR The Attempt at a Solution Req...

Car A is dropped at 4000 ft where directly below is an x on the road. At the instant Car A is dropped Car B is exactly 4000 ft from the x driving down the road at a constant velocity of 142 mph. Does Car B make it past the x in time to avoid disaster? It's such a simple kinematics problem...

Does anybody happen to know what it is, or how to find out the voltage drop of a particular transistor?

Hi, Which equation should i be using to find the pressure drop across a channel. I know the length of the channel, the hydraulic diameter and the reynolds' number. Thank you

Dear All, I’m facing some problem when I try to determine the total voltage drop (%) from the source to the load. Assume the condition as follow: 1. DB-A is serving 3 number of individual load (#1,#2 and #3) , each 100m away from DB-A, single phase, 5kw, pf=0.85, V=240V,by using...

Hi guys, i want to ask why is there pressure drop across valves? Because if you look at bernoulli's equation, the head will be the same in 3 points, before the valve, at the valve and after the valve. The only thing changes when a fluid flow through a valve is its pressure and velocity at the...

22 Dec 2009 21:16 Voltage drop question Hi All; Total noob, first post:smile: I'm working on a small robotics project. I have an embedded computer (5V) and 2 motors with a controller. It's all powered from a 4.8V NIMH battery. The problem I'm having; As the battery gets...

Im working on a project that involves me making a electrical circuit that will supply initially around .52 amps of current for and then drop the current to at least .40 amps of current to a actuating wire that uses current to cause wire to contract. The way i have my circuit made is that i have...

Homework Statement Prove that for a line having resistance R, and reactance X, and supplying load of P+jQ has an approximate voltage drop of: Vr = [RP+XQ]/Vs Homework Equations none given. The Attempt at a Solution I made a diagram, with R, X, and P+jQ in series. Vr is the...

Is voltage the potential energy difference between source A and B in a circuit? If so in absense of resistance and the presence of a 3V battery does point A have 3V to begin with and at point B there is 0 volts. Is all potential energy converted to kinetic energy when moving from A to B? A is...

the depletion region is resposible for voltage drop all that is fine but in forward bias there is no depletion region hence there can be no voltage drop but it is mentioned in my book that the voltage will drop by .7 volt how come this can happen also i have many doubts in transistor...

Homework Statement A spherical drop of oil, 1 mm in diameter, falls on a water surface. The oil spreads out to cover a circular patch of diameter 60 cm. The oil spreads out until it forms a uniform layer on top of the water, only one molecule thick. What is the thickness of this layer...

Hi Experts :!), I tried to use a 5v dc voltage source to power a normal handheld 3v radio using a resistor to regulate the voltage. The voltage drop across the resistor seems to fluctuate constantly by about +/- 0.8 volts. So, the voltage drop across the resistor fluctuates between 1.5v...

I recently made a small version of Lord Kelvin's "thunderstorm" while I was bored at school one day, and I'm still mystified as to how such a large potential gets generated. I have two hypotheses, but I haven't had a chance to test them yet and I was wondering if anybody knew how the generator...

Dear all, I am trying to solve a simple model with Comsol to find the pressure drop in a rectangular channel W=5mm, h=0.6mm, L=10mm. When i try to set the inlet velocity to 0.5m/s the solver shows the error message "Maximum number of Newton iterations reached". The solver works fine if i set...

Homework Statement For my Calc based Physics class we will be given an egg, a required height and a bungee cord (non-linear). We're to have already come up with a formula for this bungee cord to compute the required length so that we'll be able to drop the egg from the height and come as close...

What is better to possibly get a C in a class or just drop it and retake it after I transfer somewhere else? I have a really bad Linear Algebra course that is taught by an inept instructor who is well "past his prime." Complemented with a very obscure and difficult to understand book. I've...

Say we have a rectangular wire frame about 7 inches in size, see: http://www.schillereng.com/EggDrop1.jpg Let an egg of mass m, say 40g, be suspended in some type of "seat" as in the above jpg. with rubber bands going from the the eight corners of the frame to the egg seat. Let us say the...

Voltage drop is how much energy a device uses. Wattage is the rate of energy transferred into the device per unit of time. Aren't both essentially the same thing? Or am I just confused?

Homework Statement A Ball is dropped onto a step at point A and rebounds with a velocity Vo at an angle 15 degrees with the vertical. Determine the value of V0 knowing that just before the ball bounces at Point B its velocity VB forms an angle of 12 degrees with the vertical. Homework...

Homework Statement A ranch hand sitting on a tree limb wishes to drop vertically onto a horse galloping under the tree at the speed of 9.28 m/s and the distance from the limb to the saddle is 3.84m. a) What must be the horizontal distance (m) between the saddle and the limb when the ranch...

Homework Statement I have a couple of questions about one of my homework assignments any help would be greatly appreciated. 1. How do you find the Voltage drop of a Resistor in an AC Circuit is it similar to DC? V=IR The Resitor value is 68 ohms and there is an 80mH inductor in front of...

A Major league pitcher can throw a ball in excess of 41.3m/s. If a ball is thrown horizontally at this speed, how much will it drop by the time it reaches a catcher who is 17.0m away from the point of release? So Ay=-9.8 X=17m t=? Vox=0 V=41.3 y=(Vy^2-Voy^2)2g I thoguht i would use this...

Hi guys I am currently using Comsol to model a single rectangular channel, a typical one found in a fuel cell (with symmetry boundary). Dimension of the inlet and outlet area is of the order 10e-3 and the length of the pipe is 0.1 m. I am having difficulty getting the expected result. The...

Basically I am taking the lab concurrently with the class, unfortunately we learn how to do the lab a few weeks after we do it so its becoming quite depressing. I could probably slide out of it with a B or C and get absolutely nothing out of it. I should have waited to take it butI didnt realize...

Hi, 20m straight length horizontal pipe (60 mm internal diameter), steam flows at rate 0.5 kg/s, at midpoint there is a valve in the line. inlet pressure to this section of line is 5 bar (gauge), pressure at end of line is 3 bar (gauge). mass quality of steam is 0.8 and 2 phase flow occurs in...

Hi, I've been looking at some example solution and still haven't found the physical/mathematical explanation for the given solution. Problem: Due to slow satellite stabilization rotation there are big differences between maximums and minimums of received signals. Calculate the power...

Homework Statement Solve for all unkown i's and V's EDIT: there is a seventh resistor that is right under the negative side of the source. Vs=12V Homework Equations V=IR The Attempt at a Solution I got the I's by finding the voltage across the entire 2 loops to equal 0, then...

Homework Statement Determine Req, the missing I's and V's? Homework Equations V=IR The Attempt at a Solution First problem is that I thought I learned that R2 and R3 are in parallel so you have to use the recipercal rule, but looking back at my notes for Interpetation...

Homework Statement A small drop of water measuring 0.6 mm in diameter, hangs suspended above the ground due to the Electric field of the Earth (140 N/C). How many extra electrons are on the drop of water? Homework Equations i know k=8.99 x 10^9 abs(f)=K((q)/(r^2)) The Attempt at a...

As my name indicates, I enjoy archery (specifically bowhunting). I am in the process of determining the ideal weight (measured in grains) for a set of arrows that I am making. I want to have the heaviest arrow possible (i.e. for optimal momentum and penetration), but I want to still have...

Homework Statement We all know the egg drop, and I am stuck as to what to do with the extreme little amount of materials we are allowed to use. Here they are: 1 regular supermarket egg 5 sheets of printer paper 1m of scotch tape We are to drop it once from the ceiling of our...

Hi I am designing a heat exchanger. I know the mass flow rate required for cooling. I have calculated the pressure drop for current design. How do I work out if the size if the heat exchanger can handle the flow rate ? Does the mass flow rate depend on the size of the heat exchanger tubes ...

Someone on YoutTube stated... Each magnetic pole drops off by 1/R^2. Once you get away from both poles (Cavendish setup) they they start canceling each other out and it ends up as 1/R^3. Comments? Here's the link if you need backup info...

Hello, We did a lab in class yesterday and we are expected to write a report and graph our results. The lab was a simulation of the Millikan oil drop experiment. We used graphing calculators to do the simulation and took down 15 results. One thing i don't understand is how to come up with the...

I was bored, my internet was out (from the rain), and so was TV. So all I could was sit there and think... So I started asking myself, how much energy does a single rain drop have and how much electricity could THEORETICALLY (100% efficiency) be produced from falling rain? So when my internet...

There are situations when a water drop falls on a really hot metal surface and, instead of evaporating, it kinda bounces on the surface. Why?