# Search results

1. ### Calculation of magnetic force on a wire

Hi, I would like to know if it is possible to move a steel wire against frictional forces using a magnet. What would be the approach of calculating the force acting on that thin wire. I would know the dimensions of the wire and the dimensions of the magnet. What other values should I find...
2. ### De - Ionized (DI) Water

Hi, How long does de-ionized water remain de-ionized. After what amount of time would it start geting ionized again. I understand that it would greatly depend on the container in which it is kept and the environmental conditions. However, the order of the time would help me. Thanks.
3. ### Variable pressure

I need to introduce variable pressure into a system. I was planning on using piston pumps which if i run at low rpms would result in controlled fluctuating pressures. Am i doing something wrong?
4. ### Humidity and its effect on air properties

Hi, I would like to find the properties of humid air at different humidities and different temperatures. What sort of charts should i consult? I tried looking at psychrometric charts, i'm not sure if i'm reading the correct thing. Thanks
5. ### Pressure Temperature Relation

Is there a relation between pressure/velocity and temperature for liquids. Something like the ideal gas law for fluids in general?
6. ### Vapor Quality calculation

Water is being used as a coolant by flowing through a channel. I know the mass flow rate of water. And i know the inlet properties of water. I also know that the water is coming out of the channel at a vapor quality of 1. How do i calculate the heat flux that the water is subjected to during...
7. ### Does the viscosity of air change with change in the degree of humidity

Does the viscosity of air change with change in the degree of humidity at room temperature?
8. ### Flow development

Homework Statement The following stream function holds for a certain flow of water at 20 C. psi = 4y - (y^3)/3. Is this flow fully developed? Homework Equations psi = 4y - (y^3)/3. The Attempt at a Solution How am i suppose to tell if a flow is fully developed or not from...
9. ### Rotation of flows

Homework Statement If liquid contained within a closed circular cylinder rotates about the axis of the cylinder, prove that the equation of continuity and boundary conditions are satisfied by V = (omega) x r, where 'omega' is the angular velocity of fluid supposed to be dependent on time only...
10. ### Presentation on Permeability

Hi, I'm working on a presentation on Permeability. I need some basic information to start off. However, when i google permeability, all i get is magnetic permeability or permeability of the different types of soils. I'm more interested in the permeability of particles through semi porous...
11. ### Fully developed flow regime

Is it possible to look at a stream function and decide whether it is fully developed or not?
12. ### Pressure drop in pipe flow

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
13. ### Flow problem

Homework Statement A flow is described by velocity field V=(ay)i + bj, where a = 1, and b = 2. Co-ordinates are measured in meters. Obtain the equaion for the streamline passing through point (6,6). At t = 1 seconds, what are the co-ordinates of the particle that passed through the point...
14. ### Calculating rate of change

Homework Statement The concentration c of fish away from a feeding point in a lake is given by c(x,y) = 1/(x2 + y2). Find the total change of fish concentration detected by an observer riding a boat traveling with a speed u = 10 m/s straight away from the feeding point. What is the...
15. ### Coin phone

The pay phones in which we have to drop the coin in and then we are able to make calls. These are often evident at railway stations and other places. Does anyone have any idea as to how they work?

could someone let me know the problems being faced while using disc brakes in any sort of vehicles?
17. ### Maximum range (RFID) can function

I need to know the maximum range in which a radio frequency identification device (RFID) can function. What is it limited by?
18. ### Pressure inside an ic engine

Could some one tell me if there is any method to find out the instant pressure inside the combustion chamber of the internal combustion engine. I plan to change the way engines work if the pressure can be monitored.
19. ### Pulse jets and ram jets as part of my course on jet propulsion

i was reading about pulse jets and ram jets as part of my course on jet propulsion. all i was told was that they are aero-thermo-dynamic-ducts. couldn't understand what they mean. checked google, but the articles i got were vague. could someone explain what aero-thermo-dynamic-ducts are?
20. ### Car tires

Is it true that there are metal wires in the tires of two wheelers where as car tires come with metal plates inside them?
21. ### Rocket nozzle

why do we need the pressure at the exit of nozzle to be equal to that of the outside pressure?
22. ### What exactly is a zero radius turn vehicle?

Well for my project in 6th sem, i'm planning to make a zero radius turn vehicle. What i understand by a zero radius turning vehicle is that it should keep the centre of mass at a fixed position and then rotate so that it moves 180 degrees. That is the maximum movement i should be able to show i...
23. ### The load of a generator

You see i came across this question during my viva in my practical examination. Well the question was that when we increase the electrical load on a genarator, does the resistance in the load increase or go down for the load to increase. we notice that the current remains constant....
24. ### Fighter aircraft maneovres

We learn from a very early class that the aerofoil design of the aircraft wings provide it with the required thrust to keep the plane afloat. It is the only upward acting force. And the reason cited for is that the design allows air to rush faster over the upper portion of the wings compared to...

When we take the turn in a car at a high speed, the turning radius is pretty big. Similarly, at supersonic speeds, the turning radius of aircrafts would be huge. Could any one tell me the turning radius of aircrafts as such speeds and the minimum turning radius of any aircraft.....
26. ### Wenkel engine

Why do we not use Wenkel Engines? THey are easy to build and use. Why do we not use them in the practical world. Or is there any component in which the wenkel engine is used and i'm not aware of?
27. ### IC engines

Could you tell me where to find the retailer of IC engines of 3.2 cc size in Delhi and how much it would cost. I have been told by someone that we would be able to get it in Preet Vihar. Could any of you give me some idea in this regard.
28. ### Power of an engine

I am required to design an ATV with the use of a 3.2 cc IC engine. Can you tell me the factors affecting the power delivered and the speed of the ATV. How should i go about the calculations.
29. ### Calculating the power

I have been working on a new idea. However, i could not find out how to calculate the r.p.m of the power source. How do i do it.
30. ### Alternative fuels

Why can we not use normal alcohols such as ethanol or methanol for the purpose of running our vehicles? is there any particular problem?