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  1. E

    C/C++ Guide to C++ Programming For Beginners

    I don't understand what you are talking about or want to create in C.
  2. E

    Q: how variable declaration & initializing in C Language.

    In your structure you forgot the semicolon after the closing curly brace. C is a good start to learn the basic libraries, functions, and the syntax if you want to then learn C++.
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    Q: how variable declaration & initializing in C Language.

    Declaring and initializing a variable is simple and easy to do. Declaring is by defining a variable and the type of data that the variable is going to store. The main types of variables are: void (void), character (char), integers (int), float (float), and doubles (double). Here's some type of...
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    C/C++ Guide to C++ Programming For Beginners

    I think you can the basics of C++, but you should get a book to understand it fully.
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    Find thermocouples in a store

    Can you show me how you make a thermocouple. I do understand what you're saying only that I would like something visual to make reference on so I know I'm doing it correctly.
  6. E

    Find thermocouples in a store

    Is there a diagram on how to make one. Because I've been Googling thermocouple but I didn't get a solid description on how to make one except that you need a difference of temperature for it to work which I think I know where to get the two different temperatures. Thank you for your help.
  7. E

    Find thermocouples in a store

    I want to know where can you find thermocouples in a store to buy or can you make them by using house hold items? The reason why I want to buy or make one is to use it during summer to generate electricity durning the hot weather.
  8. E

    Nedd help finding weight over length

    If we convert 1100 lbs we get approximately 498.9567 kg and then times the Fg which is 9.8 N which equals 4,889.776 N. The you will have to split the problem into a y and x component to get the force the the table exerts when you lift it 35 or 40 degrees up.
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    Resistance on a Wire.

    I want to know, how do you calculate the resistance of a copper wire with a length of 0.35 meters (1.148 feet) long with a diameter of 0.8118 mm (20 AWG). I found that the resistance of a copper wire in one foot is 98.496 [tex]\omega[\tex] and will be two 1.5V AA battery, so the current running...
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    YOU: Fix the US Energy Crisis

    Even though the area is off limits, the nuclear test sites are under federal land which are under the Military sovereignty unless Congress allows nuclear waste to be stored there. Its off limits to the public, not to the Military or to federal government.
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    A Star's Life, (Full Explanation)

    Even if a person did tackle this in one shot, it will be far too much explanation where you could just easily read it on a book dealing with the topic. People are going to read the post, just they aren't going to tackle one question at a time. There are different types of of a stars, not just...
  12. E

    Question on electromagnetic repulsion

    An object cannot be attracted, but yet be repealed at the same time. You should have at least posted some dimensions of the magnet (length, width, mass, etc.) and the type of battery that you are using and the current that it delivers.
  13. E

    Check my arithmetic for this formula.

    Ok, yes it does clarify. Ae is meant to multiply with (Pe - Pa) not to divide F - (Pe - Pa), which is not dividing but multiplying. Thank you for your help.
  14. E

    Capacitor Battery

    Like uart said, you haven't specified the amount of power needed to operate or the current in one hour that you need in order to find the amount of charge before going to calculate the capacitance for the capacitor that you need. Voltage is one piece of the puzzle to find out the capacitor that...
  15. E

    Lightning as a measure of global warming

    In been a correlation between thunderstorms and Global Warming is hard to actually know. You have to do research and try to find if there are any lurking variables that will explain the phenomenon. Mostly because you are dealing with nature, there is more than meets the eye. Is like saying...
  16. E

    Check my arithmetic for this formula.

    I don't get what you are saying by loosing Ae from (Pe - Pa). I get wat you are saying after the and part of the sentence. Can you change the place of Ae because of order of operations, you will have to multiply first before you can add: + Ae * (Pe - Pa)?
  17. E

    Check my arithmetic for this formula.

    I have this formula: F = qVe + (Pe - Pa) * Ae; I want to get q by its self. This what I did to get q by its self. F = qVe + (Pe - Pa) * Ae \frac{F - (P_e - P_a)}{(A_e)} = \frac{(V_e * q)(A_e)}{(A_e)} [( F - (Pe - Pa)) ÷ Ae] ÷ Ve = q This is how I got q by itself in order to solve for...
  18. E

    Voltage and Current Clarification

    That's what started to think about the resistance that the hair dryer has. One way to get the power back to 1.8kW is to get the current to 7.5 amps. The resistance then should be at 32 \Omega because \frac{V}{I} = R. Because consumer products you can't actually change the resistance, the...
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    Voltage and Current Clarification

    Ok, now I get what your trying to say for voltage. So, like my lamp that needs to run at 0.06kW and the standard voltage is 120V. The current that will be 0.5amps to meet the 0.06kW need to run the lamp. One thing that I don't get on your explenation, if the hair dryer uses 15 amps to get the...
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    Voltage and Current Clarification

    Ok, thank you for the clarification, both of you. This is my last question. When you look at the voltage of an electrical device, is it the energy needed to run the electrical device when having the proper current? This what I have in my book: " One volt is the potential difference between two...
  21. E

    Voltage and Current Clarification

    That's what my teacher said about Coulomb's Law and how its expressed. This is my other approach to find the charge. Let's say you have a current of 4amps. Time is normally expressed in hours for electronic equipment (mostly) so you just multiply the current with the time to get the charge like...
  22. E

    Does photons have a mass?

    Photons in my perspective, is the light or radiation emitted by something like a light bulb to our Sun. The smallest mass that we have discovered is the electron that orbits the nucleus of an atom. Anything can be measured in a scientific way, big or small. They may be exact or an approximation...
  23. E

    Global Warming or Ice Age?

    In order to prove that we are heading into an ice age with global temperatures rising?
  24. E

    Using a plasma arc instead of fission for a reactor style rocket

    But if you want to have a manned mission to another planet, you want to get and come back in specific time frame, but for a unmanned mission it will depend. An ion engine sounds better because it yields more thrust than a solar sail. If can live on the moon, that's the perfect place to create a...
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    Voltage and Current Clarification

    Oh, ok. To get the force, you use Coulomb's Law, but I'm not sure if the distance is the length of the wire or how far you are going to do the work. That's what has me puzzled. The formula that I have for Coulomb's Law is: F = \frac{kQ_1Q_2}{d^2} To find the work, you use the force that you...
  26. E

    Voltage and Current Clarification

    Ok, let's say that you have a charge of 10μC and you wanted to find the work so then you can find the voltage. Do you do the W=Fd formula to find the work?
  27. E

    Using a plasma arc instead of fission for a reactor style rocket

    The solar sail concept for a new way to propel a spacecraft to other planets, like Mars, will take too long to reach. But to travel to a celestial body like a comet or farther than a soar sail will be good to use because it continue to increase as long as there is light, from the Sun for this...
  28. E

    Voltage and Current Clarification

    So, like my lamp that has a max of 60 Watts. To find the Work you do Work = Power * time (in hours). It will look like this: 60W * 3600s = 216,000 Joules or 216 kJ The amount of work is 216 kJ that then gives you 60 Watts of power in one hour. The only thing that I'm confused is finding...
  29. E

    YOU: Fix the US Energy Crisis

    The Obama administration wants to end the recession as fast as possible, even though from the stimulus pack, we are more into debt than ever before. The shots where already fired here in California where both, I think, propositions for research and to start creating renewable resourses didn't...
  30. E

    Resistor Concept: Series & Parallel Circuits

    Ok this what my book says about resistance: "The principal applications of resistors are to limit the flow of current and, in certain cases, to generate heat." The formula that you have V = IR I think you mean by conductance which has a symbol of G which is expressed my this formula: G =...
  31. E

    Voltage and Current Clarification

    I need some clarification with voltage and current and how you calculate the voltage and the current. Also when you are given the voltage and the current, how to find the charge and the time for the current; and the work and the charge for voltage. This is the formulas that I have for...
  32. E

    Using a plasma arc instead of fission for a reactor style rocket

    First, a nuclear rocket will not be an effective rocket; furthermore if it uses fission or fusion. Rockets don't have a high reliablility than a conventional airplane flight. A rocket like that will be too heavy to lift of the ground with all the shielding needed for radiation to be contained...
  33. E

    Physical properties of High-temperature reusable surface insulation tiles

    The tiles are, I think, ceramic tiles that do not conduct heat which in turn have high melting temperatures. From the ballistic missiles to the heat shield of the CM, Soyuz capsule, etc. have a heat shield that doesn't conduct heath in order to survive re-entry. Another factor is that the tiles...
  34. E

    Mass flow rate formula

    When you are going to calculate the mass flow rate, which formula do you use? Do you use: mdot = \frac{A p_t}{\sqrt{T_t}} * \sqrt{\frac{\gamma}{R}} * M (1 + \frac{\gamma - 1}{2} M^2) ^-^\frac{\gamma + 1}{2(\gamma - 1)} or mdot = r*V*A?
  35. E

    Exhaust Velocity Calculation

    Please check my calculations for the exhaust velocity of a rocket that uses Nitrogen Tetroxide (N2H4) & Aerozine 50 as its propelants. This is the formula that I'm using to find out the exhaust velocity: ## V_e = \sqrt{{\frac{T*R}{M}}*{\frac{2*k}{k-1}}*[1-(P_e/P)^(^k^-^1^)^/^k] } ## Ve =...
  36. E

    Mass flow rate formula

    Yeah, that's the mass flow rate formula to find the flow rate. Yeah, this are the graphs that I'm looking at for the propellants that each have a unique Optimum Mixture Ratio, Adiabatic Flame Temperature, Gas Molecular Weight, and Gas Molecular Weight. I'm just looking over the Adiabatic Flame...
  37. E

    Projectile Motion parabola effect

    OK, thank you for your help, LowlyPion.
  38. E

    Mass flow rate formula

    I think this might be another possibility: \frac{m_f - m_i}{\Delta t} Ok, I read over the link that you send me and I found out that mass flow rate units are kg/s. So I think the you subtract mass final from mass initial and divided over the period of time. I'm not sure yet, but this is my...
  39. E

    Rocket Engine Exhaust Velocity

    That's the reason why the F-1 engine operated at 69.085 atm and the SSME operate at 186.922 atm because the difference of their fuel. The SSME can obtain a higher pressure because the Adiabatic Flame Temperature for kerosene is higher than hydrogen at low pressures. What temperature is 0.7 Tmelt?
  40. E

    Rocket Engine Exhaust Velocity

    Yeah, it is greater than the SSME engines and also the F-1 engine. So the more pressure there is in the combustion chamber the heavier the engine is going to be to widstand the high pressure and temperature of the engine so it doesn't burst or melt. There is a limit on how much pressure you can...
  41. E

    Mass flow rate formula

    I want to clarify this because I'm still not sure how to find the mass flow rate, for instance from a rocket. I still puzzled from the formula that describes the mass flow rate which is \frac{dv}{dt}. This the formula that I'm currently looking over but I'm not sure if its this formula to find...
  42. E

    What will happen to Earth when hit by a Neutron Star at the Speed of Light?

    Kinetic energy isn't going to be transferred from one place to the next on impact. But still at that velocity and that massive it is going to be destructive. Ok this is what I got for the KE again: 1.2066*1047. Either way that's a huge amount of energy. Can you please post the collision formula...
  43. E

    Rocket Engine Exhaust Velocity

    But is there away to calculate the Optimum Mixture Ratio, Adiabatic Flame Temperature, Gas Molecular Weight, and the Specific Heat Ratio when the Pc is more than 250 atm?
  44. E

    Orbital Speed of a Satellite

    The velocity is an approximate, but like you said it isn't exact. I agree that the 7,700.27 m/s does look too precise. I was using my book to refer on what the units to use for the velocity which gave m/s. For a rocket to reach 7.7 km does it have to reach that velocity in a period of time...
  45. E

    What will happen to Earth when hit by a Neutron Star at the Speed of Light?

    Thank you for that correction. The next step now is to divide it by 0.5 to get the final answer. But if the star did, it will destroy the Earth or make it inhabitable after a collision like that which unlikely to happen which will need something to accelerated to the speed of light.
  46. E

    Orbital Speed of a Satellite

    Can you find the orbital velocity of a planet which a satellite has to obtain in order to revolve around the planet with this formula: v = \sqrt{\frac{Gm_E}{r_E}} G = gravitational constant 6.67*10-11 mE = Mass of a planet rE = the radius of the orbit rE = h + r h = height of the...
  47. E

    Black Hole time dilation

    Remember that matter cannot be destroyed. The matter doesn't seemly disappear into thin air, so where is your part of the story that the black hole gobbles up the matter everything and doesn't have a limit? The matter gets crushed with the enormous gravity of a black hole, but does it grow in...
  48. E

    Projectile Motion parabola effect

    This is my final question. When you find the maximum height of the ball and also the time, can you plug in the time to the equation: ymax = y_i + v_y_i(\frac{v_y_i - v_y}{g}) + \frac{1}{2} (-g)(\frac{v_y_i - v_y}{g})^2 and still get the maximum height? The time is 0.84 seconds.
  49. E

    What will happen to Earth when hit by a Neutron Star at the Speed of Light?

    You can find the amount of energy that the Neutron Star is impacting the Earth using the KE formula: KE = mv2 m is the mass of the Neutron Star which is 1.35 solar masses (2.685042*1030) v = 299,792,458 m/s (speed of light) KE = (2.685042*1030)(299,792,458 m/s)2 KE = 2.4132*1047Joules or...
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    Rocket Engine Exhaust Velocity

    I've looked over the problem from http://www.braeunig.us/space/problem.htm#1.5 and I'll like to figure out how to find the chamber pressure of a rocket engine without actually having to test an engine. I'll be using the SSME to find it's exhaust velocity. The chamber pressure of the engine...
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