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    7-segment display 3-to-8 decoder logic circuit (please help, thank you)

    So it is obvious that you don't understand the problem and you would get a failing grade for this homework. There is no "random number generator" called for, but rather for the "sequential display" of a particular string on numbers. So the input to the logic circuit is the sequential count...
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    7-segment display 3-to-8 decoder logic circuit (please help, thank you)

    Now I thought that the secret in life was to recognize a source of bad advice and not take any of it. Do you suppose that the reason for this task is to obtain a unique display driver? Or might the real purpose be to get the student to think about implementing logic functions with decoders...
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    Energy Lost Due To Friction

    In post #15 @duke37 stated "The speed at the end of the descent will be double the average speed if the acceleration is constant."
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    Energy Lost Due To Friction

    @duke37 already explained that aspect. You should read his post above. Very informative.
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    Energy Lost Due To Friction

    But that is irrelevant. For constant acceleration the velocity is a linear function of time. The average speed is not the velocity at the mid-point distance, but rather the velocity at the mid-point in time, or more simply the total distance divided by the total time.
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    Energy Lost Due To Friction

    The loss of potential energy to friction is directly proportional to the length of the incline. And the distance is quite easy to measure.
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    Energy Lost Due To Friction

    Yes, there are several approaches to the solution. One method is to consider the forces acting on the trolley and use the resultant acceleration to analyze the motion. Another method is to consider the conversion of potential energy to kinetic energy and friction loss. In the first case the...
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    Energy Lost Due To Friction

    One can use the kinematic equations for free fall if the acceleration is constant. http://www.physicsclassroom.com/class/1DKin/Lesson-6/Kinematic-Equations-and-Free-Fall The acceleration will be constant if the net force acting on the object is constant. So you need to analyze the forces...
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    How do I attach this kind of chip to a breadboard?

    I would just treat each of those 10 pins as an opportunity to wire-wrap. Place the chip on top of a wire-wrap socket, then use short pieces of WW wire to connect each chip pin to the socket pin below it. Plug the socket into the breadboard.
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    Energy Lost Due To Friction

    That method will give the average velocity; however, when accounting for the conversion of potential energy to kinetic energy given by the term ½mv², it is the instantaneous velocity that must be used. Are you sure that the average velocity equals the instantaneous velocity? Also, the rolling...
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    7-segment display 3-to-8 decoder logic circuit (please help, thank you)

    I understood the instructions to say you were not to build the 3-to-8 decoder but rather use the output of the 3-to-8 decoder to drive the logic circuit which you are required to build. So the logic circuit will have 8 inputs and 7 outputs, and only one of the 8 inputs will be active at any one...
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    Energy Lost Due To Friction

    If that means you can measure the trolley velocity at the bottom of incline, then I can't imagine what the problem is. However, if the trolley acquires much velocity on the downward run, then one would need to account for the effect of air resistance in addition to the friction of rolling...
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    Confusion between cap charge and discharge

    I would not call it a 'recipe' - it is just a recognition that all exponential curves are governed by the time constant, the total change, and the zero value. You just have to be smart enough to pick those values out of the circuit to form the equation. The capacitor current is also an...
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    Confusion between cap charge and discharge

    Any first-order transient is going to be an exponential curve. But getting the equation for the curve takes a series of considerations, as follows: 1. Find the time constant, τ, from the circuit. 2. Determine whether the voltage (or current) will be rising or falling, then use the charge curve...
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    series parallel RC circuit help

    I would have thought that in recognition of the Duality Principle* for electronics you might have chosen, INDUCTORS! After 6τ in an RC circuit we say the capacitor is fully charged because the capacitor stores charge. But in an RL circuit after 6τ we say the inductor is, what? Do we even have a...
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    series parallel RC circuit help

    What could be simpler than a fully charged capacitor being equivalent to an open circuit?
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    series parallel RC circuit help

    Beginners need to pay their dues and learn the technical jargon of the profession. There is no other way. For the layperson who is not knowledgeable about the subject, they don't have the technical background to understand these abstract concepts so getting electronics professionals to use a new...
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    series parallel RC circuit help

    But the capacitors are "energized" from the time t=0+ onward. How is the student expected to know that the answer requires a calculation for t>6τ when the capacitors have become fully charged? Note that the technical jargon "fully charged" means as energized as the capacitors will ever become...
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    series parallel RC circuit help

    Webster's New World College Dictionary gives the relevant definition of slang: the specialized vocabulary and idioms of those in the same work: now usually called shoptalk, jargon. I don't seem to have any problem with electronics professionals using specialized technical jargon. So we should...
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    series parallel RC circuit help

    My physics textbook, "College Physics" by Sears & Zemansky, has this to say: The net charge on the capacitor as a whole is, of course, zero, and "the charge on a capacitor" is understood to mean the charge on either conductor without regard to sign. It does not seem too difficult to understand...
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