Recent content by cpatel23

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    Probability Question - Joint density function

    Before I begin, here is the question: If the PDF of two independent random variables X and Y are: f(x) = exp(-x)u(x) f(y) = exp(-y)u(y) Determine the join probability density function (JPDF) of Z&W defined by: Z = X+Y W = X/(X+Y). So, I know how to solve this except for one thing. How do I get...
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    Need help with some signals/systems [easy]

    Hello. Here is the question: Are the following functions a. linear or non linear b. with memory or memoryless c. causal or non causal d. time invariant or time variant e. stable or unstable 1. y(z) = x(z) + ez I know that this function is memoryless, causal, and unstable...
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    Chemistry Problem: Solving with Molar Mass & Isotope Abundance

    Hello. I am doing a chemistry problem but it is mainly mathematics Here it is. A little info that is useful to this problem. Molar mass is always an average, given by Molar Mass = (mass of isotope1 * abundance of isotope 1) + (mass of isotope2 + abundance of isotope 2) Masses of...
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    KVL Node Voltage: Positive vs Negative Assumption in Homework Solution

    Homework Statement Homework Equations ƩCurrent(in) = ƩCurrent(out) The Attempt at a Solution ----In situations like that, my book takes the node to be a positive voltage when the voltage source is connected like above. For some reason my professor takes it to be negative, is this why my...
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    Are capacitors a viable option for storing charge in electronic circuits?

    in my own words... Voltage - from what I've learned in e&m, it is the magnitude of an EMF. Current - the rate at which voltage is transported Resistance (in terms of circuits/electricity) - something that is against the flow of current
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    Are capacitors a viable option for storing charge in electronic circuits?

    So if I had a circuit with a battery giving 20V and current flows through a few resistors. If I measure the voltage right before the current re-enters the battery, the voltage would be less then 20V, correct?
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    Are capacitors a viable option for storing charge in electronic circuits?

    Last question, I have a circuit like so http://i.imgur.com/WxSzV.jpg When I let the capacitor fully charge it comes out to ~7.2V (Battery is at 8.7V). The resistors are 180ohms each Now when I remove the resistors and leave the LED and capacitor in series, the voltage on the capacitor will...
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    Are capacitors a viable option for storing charge in electronic circuits?

    :bugeye: wow. Is there a reason why all the capacitor tanks have low voltage (sub 9V)? Are these any good? >>>=pattern&id[q]=heat+sink&x=0&y=0"]Heat Sink It says 1W, is that how much it dissipates or how much energy it requires to operate? So a rectifier doesn't completely convert AC to DC? It...
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    Are capacitors a viable option for storing charge in electronic circuits?

    Lol, please forgive me, only education I have on electronics is from my physics classes. Taking an introduction to electronics this upcoming quarter. Hopefully it can clear things up. Any good electronics books in mind that I can read until then?Also, when I use a DC voltage regulator to...
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    Are capacitors a viable option for storing charge in electronic circuits?

    What do you mean capacitors do not pass DC Volts/Amps? My multimeter gives me a legitimate reading when I measure DC voltage in a capacitor. And how can you use a capacitor to block DC current from going backwards, I always thought that is what diodes are for.
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    Are capacitors a viable option for storing charge in electronic circuits?

    I was thinking of a small scale setup (until I really get the hang of things). My initial idea was to by a dozen or so 1.2V/9V rechargeable batteries. Putting them in series accordingly to achieve a needed voltage, recharging them using solar panels. As for cost, I understand they could get a...
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    Are capacitors a viable option for storing charge in electronic circuits?

    In terms of storing back up energy (for blackouts/being self sufficient), would it be better to use a battery or capacitor. From what I've learned, batteries would be more efficient even though they have their limitations. This may seem stupid, but is it possible to store energy in a generator...
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    Are capacitors a viable option for storing charge in electronic circuits?

    Right. A camera flash circuit uses a capacitor to release a high amount of energy in a short amount of time. So that means capacitors are only good for short bursts of energy?
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    Are capacitors a viable option for storing charge in electronic circuits?

    I just finished my last physics class (e&m) and I was pretty intrigued by capacitors and their ability to store charge. I decided to take an electronics class next quarter so I bought a few things including breadboard, capacitor, resistor, diodes, motors, and so on. Now...I have a 50V 1000uF...
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