Drop Definition and 876 Threads

Homework Statement Think of a drop of radius ##R## deposited on a fibre of radius ##b(b<<L)##.Find ##{\Delta{P}}## Homework Equations The relationship between excess pressure and the surface tension is given by Yong-Laplace equation, $$\Delta{P} = \sigma{(\frac{1}{R_1}+\frac{1}{R_2})}$$ The...

I have a linear actuator that raises and lowers my snow plow blade and the wireless remote stopped working. Rather than order a new one for $200, I decided to splice into the wiring and put a momentary switch in my truck. I didn't like the remote anyways. I grabbed some wire and wired up a...

Homework Statement A drop of water fall towards the ground with initial mass [m][/0] and radius [r][/0] (assume the initial shape of that water drop is sphere). the air resistance is F=½.ρ.A.[v][/2].C (C is the drag coefficent, A is the area that the air contact with the water drop and ρ is the...

I am trying to calculate pressure losses. I've attached an image to show what I mean. Starting out tank 1 is 92.8 litres at 155 psi and when the shutoff valve is open the volume goes from 92.8 to 192.8 and so I thought the pressure would drop by the same factor that the volume increased by so...

Hi, I have a case of elevated AC Magnetic field in the house, strongest nearest the electric meter and along the service drop line connecting the house to the street power lines. Should that service drop line measure no current or fields when I shut off my main circuit breaker? it seems shutting...

I know the inlet pressure, temperature and density along with the massflow rate across the orifice and the orifice cross section. Is there a way for me to calculate the drop in pressure across the orifice?

I am trying to understand how fluids form particular shapes when put on a solid. In the two figures,what are we taking as a system for the forces? How the resultant of the forces influences the shape of the different fluids?

Assuming laminar viscous (meaning not frictionless) flow. Here is what I know about fluids flowing: You have a pressure difference between the two ends of the pipe. This causes a net force acting on the left side of the fluid in the pipe. Therefore, this incompressible fluid flows from left to...

Metals are highly effective at screening electric fields. If we place two contacts reasonably far away from each other on a piece of metal and apply a voltage bias, the charge carriers in the section that is far enough from both the contacts should be unaffected by the electric field. Why then...

In our practical world, the voltage between the neutral wire and the ground is not exactly 0V, and there's some small current passing through the wire connecting the neutral wire to the ground, how do you mathematically calculate this voltage drop?

I am trying to drop the series size so that it matches the size of the dataframe as I need to copy the index value of the series into the df but I am getting mismatch errors. df has a size of 100 but time has a size of 200 so I want to remove the extra rows in time to match df. how can i handle...

Hello Everyone, I've been trying to find an answer to this but am not getting anywhere. Any help would be greatly appreciated! I need to be able to calculate (or more likely estimate) the pressure drop I can expect when putting water under pressure if I know there is air in the system. For...

In this circuit,first there will be voltage drop in the internal resistance of the voltage source.Mostly,the voltage source is assumed ideal in circuits,however,here a practical voltage source is assumed. So,there will be voltage drop in the internal resistance of the voltage source which will...

A battery induces an electric field throughout a circuit in such a way that the electric field exists in the wire and the resistance. By moving in the direction of electric field, we expect that the potential decreases no matter we move in the wire or in the resistance. However, we only consider...

Homework Statement In Millikan's oil drop experiment on applying a vertically upward electric field an oil drop (of mass m) moves vertically downward with certain terminal speed. On applying double the electric field in horizontal direction, the drop moves making 45 degrees with the vertical...

Hello, I'm a chemist and I'm currently working on my PhD on materials science. I'm trying to determine the pressure difference necessary to achieve the desired gas flow inside a chamber. The scheme of the chamber is the following: I have a big chamber which is evacuated to 0.2 bar, and another...

Hello everybody, I'm designing a gas pressure feed system for a hydrogen peroxide - ethanol rocket engine, and after analyzing the devised injection plate, I noticed it is very sensitive to the propellants' pressure drops and discharge coefficients. Once the plate is manufactured, the only...

Hello everybody, I hope you are doing fine. I'm currently designing an injector for a hydrogen peroxide - ethanol engine, and the following formula is confusing me: Q = Cd * A * sqrt( 2 * dP / rho); where Cd is the discharge coefficient, A the total area, dP the pressure drop, and rho the...

Homework Statement I was doing the Milikan Oil Drop Experiment from a simulation this site: http://scienceclub.ucoz.com/index/0-109. I tried calculating the charge of the electron but it was from the real value. Oil Density: 920 (kg/m^3) Viscosity of Air: 1.81×10−5 kg/(m*s) Distance: 0.0025 m...

Homework Statement A safe (mass = 1.00*10^3 kg) is suspended a height (d) above the top end of the spring (spring constant = 27800 N/m). The rope holding the safe breaks and the safe falls, compressing the spring a total distance of 1.80 m. What is the initial height (d) of the safe when it...

Homework Statement Calculate the electric field given by a voltage drop of 1 V across an insulator with thickness 20 nm. 2. The attempt at a solution I am not sure which formula to use in order to obtain the electric field. I think one should use the formula E=U/d, where E denotes the...

Hello all, I have been having some problems and would appreciate any help: I have a length of insulated pipe filled with engine oil at rest, the variables are as follows: Toil: 40 oC Tair: 5 oC h1 (LO): 3600.63 W/m2/K r1 (pipe inner): 0.1 m r2 (pipe outer): 0.1095 m r3...

I'm having trouble understanding how voltage drops. My understanding of voltage is a difference in potential, with potential being how much work is necessary to move a test charge to a specific orientation. So, if we have a circuit with say, a 12V battery and a 1 ohm resistor, and I had a +1...

1. Homework Statement You’re testing the effect of a noxious substance on bacteria. Every 10 minutes, one-tenth of the bacteria which are still alive are killed. If the population of bacteria starts with 10^6, within which period of 10 minutes will 70% of the bacteria be killed? Homework...

Hi, I'm trying to determine if a compressed air system has sufficient system to feed a new load The minimum pressure required for existing loads and the current load is 7 bar. In order to determine the pressure at E i did a pressure loss calculation for the following A to B - △P start of pipe...

Homework Statement Homework Equations E = σ / 2ε E = Fel / Q The Attempt at a Solution E = σ / 2ε = 17.7*10-9 /(2*8.85*10-12) E =1000 N/C ΣF = 0 Fel + mg = 0 Fel = - mg 1000 * q = - 10-3 q = - 10-3 / 1000 = 10-6 C = -1μC Could somebody check my answer please ?

Why is the electrical potential greater before it passes through a resistor than after?

i have a pencil standing upright. How do i calculate the time it will take pencil to fall flat on ground if given a slight push to off balance. This is not homework. just thinking about it.

Greetings, I am trying to understand how to setup/solve for the pressure drop across an orifice L=3.5in The pipe diameter starts at 1in, then abruptly decreases to 0.5in for the length of the orifice, and abruptly transitions to 1in diameter. (See the attached file for an illustration.)...

Greetings, I have very little experience with fluid dynamics and I was wondering how I can calculate a pressure drop across an abrupt change in diameter of the piping used for water. Any help is appreciated! Thanks!

So I have two formulas for calculating voltage drop. The first is: Vdrop = Vin * R1 / ( R1 + R2...). This let's me calculate the voltage drop on the first resistor in a series of 2 resistors. You can also extend this to more resistors in series just by summing all the resistors. However, I do...

Hi There, I have constantly come across the fact that as fluid (hydraulic oil say) travels along a pipe you will see a continual drop in pressure the further you travel down the pipe. Am I right in saying that the pressure at any point is simply the result of the resistances (friction with pipe...

Homework Statement [/B] Homework Equations - The pressure drop equation. [/B]The Attempt at a Solution

Hey guys! So I will be doing the classic egg drop competition at school and was wondering if I could get some help. The materials I have is : 3 sheets of newspaper 5 popsicle sticks 10 wooden skewers 1m of masking tape hot glue I have to drop an egg multiple times (not sure the heights yet...

Hello Everyone, Can someone please explain to me how I would go about verifying the External Static Pressure of a pump that feeds a pressurized fire fighting network with loops in it. An image of the network is attached. I'm not being able to grasp the concept of pressure drop in a pressurized...

-Suppose that drop of some fluid ,with which water is miscible, that has higher density than water is dropped in the glass of (still) water. Forces acting on the drop are gravity and drag force (viscous resistance, Fd=-bv, where v is the velocity of the drop, and b is a constant that depends on...

I have wired in series: + of 9V battery --- + of 1000 uF capacitor --- 660 Ohm resistor --- + of a green LED --- - of the 9V battery. Remark: the 9V battery is a bit depleted 7.8 V unconnected. Voltage drop across the capactor is 6.5V, across the LED is 1.5V but 0V across the resistor. Why...

Good morning everyone! I am a Medical Doctor and have a very basic understanding of physics (Studied till high school). I was very much interested in freefall experiments and wanted to do something by myself. I was interested to see if I can demonstrate the lack of gravitational pull during...

Homework Statement Calculate the charge on each oil drop and determine the elementary charge on an electron given the following: Voltage (Attached) d (Distance between two charged plates) = 0.10m m (Of the droplet) = 1.57x10^-15 kg g = 9.8 kgm/s^2 Homework Equations q = mg*d / ΔV The Attempt...

Homework Statement Homework Equations I am not sure exactly what this question is asking for, especially in regards to the voltage drop. How would the graph of voltage drop vs Rmax-Rmin be any different to what is already provided? The Attempt at a Solution

In my experiment, I intended to find out how the change in the bar magnet drop height from solenoid affected the emf induced in the solenoid, however, I am unable to come up with an equation that shows a relationship between the two variables. I have thought of Biot-Savart law, but I do not...

Hello all, I am a senior electrical engineering student at Purdue University and I am working on my senior capstone project. One of the aspects of my project is to measure voltage and current waveforms as well as the relative phase shift between them. I need to get these waveforms into a data...

This is from *Statistical Physics An Introductory Course* by *Daniel J.Amit* The text is calculating the energy of internal motions of a diatomic molecule. The internal energies of a diatomic molecule, i.e. the vibrational energy and the rotational energy is given by...

Mod note: Moved from Science and Math Textbooks section, so is missing the homework template I am doing an egg drop challange and we aren’t allowed to have a parachute. I asked and I put my egg in a cup hot glued to the inside of an upside down styrofoam bowl. How do I keep it from flipping? We...

Homework Statement I am practicing diode circuit analysis for an ideal diode model and constant voltage drop model.I have an initial circuit shown here: Which I then redraw to look like this: I want to make sure my process in redrawing this was correct. When I attempt to get current through...

I have a system where pipes run 24l L/min of water @60 degrees through 3 manifolds and those manifolds distribute the water over 8 heat exchangers. Every heat exchanger requires 1 L/min, and has a resistance of about 1.333 KPa per heat exchanger at that flow (2 meter @ 9mm diameter + 2...

Does when why increase source voltage tu compensate losses why also increase voltage drop?. For example why increase current (reduce load resistance) and as side affect why increase voltage drop and then why increase source voltage tu counterbalance losses does also when why increase voltage...

Homework Statement An inductor of negligible resistance and an inductance of 0.2 H is connected in series with a 330 Ω resistor to a 12V d.c. supply. Determine: (b) the voltage drop across the inductor after two time constants(c) the voltage drop across the resistor after three time...

I love physics. Well, modern physics mostly, still physics though. It's amazing seeing how much there is we don't know and how we got to understand what we do know today. I think the concepts are crazy, cool and fun. If I didn't know better, I'd say modern physics truly sounds like pure fiction...

I don't even know what part of programming I struggle with, it's everything. I read through the course material but still feel as if they are inadequate resources when trying to solve a problem. I can't even solve the most basic programming problems, it all makes no sense to me. In mathematics...