Drop Definition and 876 Threads

Hello all! I am interested in how much energy a HVAC VAV box consumes. Can anyone help me come up with the following equation? I don't need to know the exact formula, and can assume an uncompressible fluid and/or ideal gas. Been about 20 years since I have done this and am a bit rusty...

I set up a zinc-copper elctrochemical cell by placing both electrodes in lemon juice to test the ability of lemon juice to conduct a current. I used a voltmeter and attached each lead to one of the metal electrodes. What I observed was that the voltage over time given on the voltmeter began to...

i have a 24 volt buss in a machine and i need to connect an lvdt sensor to the plc i show a 1.5k resistor that is .5 watts on the lvdt. what need to find out is the voltage drop at the resistor. i formula asks for I but I but i don't have I so what might the votage drop be. answer or formula...

Hi! What is the potential energy of electrons converted to, in a circuit? I'm asking this question because I don't really understand the concept of voltage drop across some element. If I have a series circuit with a 10V battery and two equal-in-magnitude resistors, then the potential...

Homework Statement What is the voltage drop across the 1000 Ohm resistor when capacitor is fully charged? Homework Equations V(t) = {V_i}*e^{-t/RC} = {V_i}*e^{-t/Tau} The Attempt at a Solution In RC circuit experiment, initial is 9V and final is 2V. The voltage drop should be difference...

I have seen this topic in other threads before, but I have not found an answer that eliminates my confusion. I know that electric potential is defined so that only the position of a charge with respect to a field determines the quantity of the electric potential (voltage). This allows us to...

Hi, what happens when I have a single pipe with pressure 1bar. I split this pipe into 3 equal pipes with equal diameter. What will be my pressure at the ends of these 3 equal pipes ? From what I have been reading on the internet it seems that the pressure will be the same on the 3 equal...

Homework Statement During measurement of pressure differences by the using orifice and an electronic transducer, we can have some oscillation on diaphragm, I try to define this effect by the calculating pressure drop from vena contracta to transducer. I say that oscillation is 30 percent (maybe...

Homework Statement Basically there are 3 plate capacitors, with a distance a between the first two and b between the last two. In between the first two plates is voltage V. A particle of charge q is released from the first plate, and when it leaves the second plate it is no longer...

Hello. The ground plane is sometimes used as current return path. If current is low frequency and amplitude is small then voltage rising due to current flow can be ignorable. However, what is return current is actually very high in both frequency and amplitude? In our lab, gas discharge...

Dear Physics Forum personnel, I am a college sophomore in US with major in mathematics and an aspiring algebraist. I wrote this email because I am having a great problem with my current Calculus III (vector calculus) course that I am taking for this Summer Semester. All of my fellow...

Hey everyone. Four days ago I didn't know anything about fluids but I started my internship and got assigned a project that is all about fluids! And I need some help, this topic can get really complicated but I'm trying to take it one step at a time. Problem Description: There is a pump...

I've been teaching physics at a community college in California since 1996. Starting around 2010, I seem to have noticed a change in the behavior of my students, which is that much larger numbers of them seem to be dropping the course because although they're passing, they want a higher grade...

Homework Statement A ball of mass m1 is aligned above a ball of mass M2 (with slight separation), and the two are dropped simultaneously from height h. (Assume the radius of each ball is negligible compared to h.) (a) If M2 rebounds elastically from the floor and then m1 rebounds from M2, what...

Hi, Einstein once showed that if we assume elementary particles to be singularities in spacetime (e.g. black hole electrons), then it is unnecessary to postulate geodesic motion, which in standard GR has to be introduced somewhat inelegantly by the geodesic equation. I don't have access to...

THIS PROBLEM WAS MOVED FROM GENERAL PHYSICS TO THIS FORUM BECAUSE OF ITS HOMEWORK-LIKE NATURE. SO THERE IS NO TEMPLATE. Pressure vessel has a electrical (coiled) furnace inside. A pressure vessel @ 550 bar @ 500 C containing argon has its gas inlet pipe (1 inch ext Diameter) that has come...

Hi, I hope this is the right section. I'm trying to figure out a rough estimate of the pressure drop in a spiral heat exchanger. The fluids both being water. My guess it it would be in terms of the surface area of the inside of the heat exchanger, and the flow rate, but I can't seem to nail...

To summarize, I am doing some drop test by hanging an object off of a fork lift forks, raising it, dropping it onto either concrete floor or some foam/dampening material. an accelerometer is placed on the object being dropped (epoxied on). if i am getting 46403.666 Newtons as the force, how...

Homework Statement I am doing an egg drop project write up, and one of the components is to draw a general egg drop device diagram, and to write down the general forces which would act upon the egg drop device, both inside it, and outside it. Any suggestions? Homework EquationsThe Attempt at a...

sand bag is dropped...i can understand that vertical acceleration is 9.8m/s^2...so vertical velocity increases in a.p (9.8, 19.6... m/s)...but this book says horizontal velocity of sandbag is constant and same as that of hot-air balloon (i.e., 12m/s)...I think the horizontal velocity should...

MODERATOR NOTE: THERE IS NO TEMPLATE BECAUSE THIS THREAD WAS ORIGINALLY MISPLACED IN A NON-HOMEWORK FORUM Viscous liquid (ρ = 1460 kg/m3, μ = 5.2×10−1Ns/m2) is pumped through a smooth pipe with a 0.1 m diameter, at a rate of 5×10−2m3/s. Using your Fanning friction factor versus Reynolds Number...

Is there an article or a place I can go to find the degree of reflectivity of a drop of pure water, at a defined distance? If it depends on wave length, then which wavelength provides the most reflectivity? I know this is a dual question.

Hello all, I'm stuck with following problem: At our plant we have a tank filled with a liquid maintained on 80°C with a steam coil. During the night the steam is switched off and the liquid temperature start to drop. Tank mass not taken into account atm. mass liquid: 20000 kg cp liquid...

Hello, I am currently a chemical engineering major and i have a question. What exactly does pressure drop tell you? i know the equations to solve for pressure drop for various situations (using ergon equation for a bed, or skin friction for pipes, using friction factor, etc etc ( is there...

Homework Statement I need help with egg drop ideas! For this project, I have to create something that will catch an egg (about 62.5 g) dropped from a height of 9.91 meters so that it will not break or crack. I also have to discuss forces, impulses, momentum, time and velocity changes of the...

Consider a wire connected to a battery. Now,potential is analogous to the energy of the particles.And potential in a resistor drops because of the friction inside the resistor(considering there is no friction along the wire and outside the resistor).So the friction determines how much energy is...

Considering that the electric field exist outside a battery in a wire,shouldnt the potential drop while we move along the wire even if there is no resistor(E=grad(V))?Because when i see diagrams of potential along the wire,they all show a constant potential along the wire until it reaches a...

Homework Statement I have to build a egg drop project out of only toothpicks and glue. I can have a plastic bag to hold the egg (and avoid cleaning up a mess). It has to weigh 40 grams or less. The egg must be dropped from a height of three meters. I attempted to build it. I had a cube to hold...

Hi I am new to fluid mechanics and I wondering if anyone can explain to me in very simple terms why friction causes pressure loss when steam is moving through a pipe? I thought the friction would slow down the fluid which will lead to higher pressure but it seems its the opposite. I was trying...

Homework Statement Homework Equations Whenever assuming a diode is "on", replace that diode with a 0.7 voltage source. Whenever assuming a diode is "off", replace that diode with an open circuit. The Attempt at a Solution The problem is pretty straightforward but the format of the circuit...

Homework Statement When you drop an object from a certain height, it takes time T to reach the ground with no air resistance. If you dropped it from three times that height, how long (in terms of T) would it take to reach the ground? Homework Equations ##x=x_0+v_{0x}t+\frac{1}{2}a_x t^2## The...

Okay. I have to do the egg drop project tomorrow and I need help with ideas for designs. Available materials: 2 sheets of printer paper 1 meter of tape I have to build something that can withstand about a 5 meter drop. Additional materials can be 'purchased' with grade points, but only more...

I've built a small voltage regulator that I can use with my breadboard or to test circuits. It is the first circuit that I've actually soldered together, so please disregard the hack job. The problem with the circuit is that when I hook up a very small load to the supply, the voltage plummets. A...

There is a post about the same problem here: https://www.physicsforums.com/threads/damped-oscilating-spring.12838/ It was helpful for solving part B. 1. Homework Statement A 10.6kg object oscillates at the end of a vertical spring that has a spring constant of 2.05x10^4 N/m. The effect of...

So I'm having trouble visualizing how voltage drops more within different parts of a circuit, such as a resistor vs. wire. I know all the general equations but the concept is hard for me to comprehend and I am stuck on one notion. So, say you have a simple DC circuit with just a resistor and...

Homework Statement The accompanying figure shows a horizontal ring main consisting of a single loop of pipe, as might be used for supplying water to various points on one floor of a building. Water enters the main at A at 50 psig and is discharged at B and C at rates of 20 gpm and 60 gpm...

Hi Suppose I have three motors connected to a single busbar which is fed by a single transformer and suppose that the current into the busbar (i.e. the total current of the transformer secondary) is known. If I wish to calculate the transformer voltage drop the I will obviously need the load...

Homework Statement Determine the voltage at each labelled point with respect to ground Homework Equations V*r1/(r1+r2) i*r1/(r1+r2) i=v/R The Attempt at a SolutionI'm doing a practice problem and I can't seem to get the right answer. I just want direction in the way to solve it, these are...

Homework Statement For my 8th grade honors science class we are currently doing astronomy. We got assigned a project where we have to create a landing module like the module that people land back on Earth in. The catch is that it has to be able to fit in a 10cm x10cm x10cm box and be able to...

Homework Statement I performed a lab with a simple DC circuit. The circuit has 4 resistors (i.e. R1, R2, R3 and R4), which is the same as shown in the attached image. When the voltages across all resistors were added, they were higher than the source. How is this possible? The KVL rule states...

Homework Statement A 3MVA 11kV/415V 3 Phase Transformer has the following parameters +ve sequence resistance = 0.00355pu +ve sequence reactance = 0.0901pu Primary PHASE current to the transformer is 55A and the load power factor on secondary is 0.85 lagging. Calculate voltage Drop The...

Hi all, I have a question about voltage drop of a battery. I understand Kirchoff's laws well, but it occurred to me that I did not understand intuitively why the "zero volts" at the end leg of a series circuit would still produce current. Theoretically you could have the majority of a series...

Is there any information out there regarding this topic? I know open source textbooks seem to be becoming popular in some places, and there is now a good amount of free textbooks (legal textbooks, I mean) online. In particular, there's an entire page of free online math textbooks on the...

Hi, I'm not sure if I'm posting in the right spot but I'm going to guess this is an easy question for you all. I'm going to give as much detail as I can, maybe too much.. My 2 family house condo has a single 2" or 3" water supply from the street. It is split to supply the first floor and...

First by ideal I mean zero resistance. I tried to verify Faraday's law in simple LCR circuit but ran into some conflicting results. Though the description below will be a little verbose, the configuration for this problem is extremely simple: assume that I put a solenoid...

Homework Statement When we write the V_0 on the right of the diagram as show below, between which two points does the voltage drop refer to? There are two nodes on the top correct? I am assuming the voltage drop refers to the two rightmost nodes. I've tried to circle the nodes. See this...

Homework Statement A freely falling water drop continually evaporates. Assuming that the net momentum carried away by the vapor vanishes, calculate the velocity of the drop as a function of time. (Assume that the rate of evaporation varies as the surface area)[/B]Homework Equations dA/dr =...

Homework Statement I am supposed to give a thevenin equivalent circuit to the one posted in the picture. Homework Equations V=IR KVL: "voltage drops around a closed loop sums to zero KCL: "current into a node equals current out of a node" The Attempt at a Solution The part I'm confused...

In the derivation of the generalized uncertainty principle (as pgs 1-2 of here), there is an anticommutator term that is dropped at the end, leaving just the commutator part...this is said to "strengthen" the relation, as both terms are positive. I don't understand this. So we basically have...

This is from question 1 of the F=MA 2012 exam: Consider a dripping faucet, where the faucet is 10 cm above the sink. The time between drops is such that when one drop hits the sink, one is in the air and another is about to drop. At what height above the sink will the drop in the air be right...