Switch Definition and 565 Threads

  1. S

    Voltage in capacitor after switch has been closed

    The drawing shows two fully charged capacitors (C1 = 2.00\muF, q1 = 6.00\muC; C2 = 8.00\muF, q=12.0\muC). The switch is closed, and charge flows until equilibrium is reestablished (i.e., until both capacitors have the sam voltage across their plates). Find the resulting voltage across either...
  2. H

    Circuit with switch resistors and capacitor

    Homework Statement For the circuit shown in the figure below, C = 7.50 µF, script e = 80 V, and R = 400 Ω. After having been at contact a for a long time, the switch throw is rotated to contact b. a.)What is the charge on the upper plate of the capacitor just as the switch throw is moved...
  3. U

    Difference between mechanical switch and a transistor switch?

    Doesn't a transistor switch need a mechanical switch? Otherwise, how does the transistor switch turn on and off? Does the switch have a "mind" of it's own?
  4. D

    Can someone explain me transistor as switch

    I want to know about the internal capacitance of transistor cbc and cbe
  5. C

    Solving Design Project w/ Thermal Switch (Statics)

    Homework Statement This is for Statics and mechanics of materials 1... In this project, we were tasked with the re-design of a cheap thermal switch that is to be a component of a low cost product. The switch consists of three metal strips that are bounded on the top and bottom by a rigid...
  6. D

    Circuit Elements: Battery, Resistors & Capacitor Charge 195μs Post Switch Open

    Three resistors and a capacitor are in a circuit with a battery: R1 = 23 Ω R2 = 13 Ω R3 = 15 Ω C = 6.2 µF V = 17 V The switch has been closed for a long time. What will the charge be on the capacitor 195 μs after the switch is opened? picture...
  7. S

    How to switch between momentum/real space

    I'm a bit confused about using momentum and real space and switching between them and some crap about Fourier series. Can someone provide some links to where i can study these. Please keep in mind that i am new to quantum physics.
  8. J

    Switch on a transformer but with no load connected

    If i switch on a transformer but with no load connected to the secondary path.Is the transformer will burn?
  9. O

    Circuit Switch Disconnecting Battery

    Homework Statement In the figure, V = 10 V, C1 = 13 µF and C2 = C3 = 23 µF. Switch S is first thrown to the left side until C1 reaches equilibrium. Then the switch is thrown to the right. When equilibrium is again reached, how much charge is on capacitor 1? Homework Equations The...
  10. K

    Optimizing Motor Start Frequency for 13000 Volt Switch Gear

    I am hoping that someone on here can give me some insight on what caused this. I have my idea; however, I would like someone to give their opinion also. At work we have a 13000 volt motor that powers our compressor. How frequent can that size motor be started without causing the motor to...
  11. J

    Wiring a Series and Parellel Switch for 12v/48v

    OK. I have 4 - 12 volt batteries. In parallel is 48 volts and series is 12 volts. I would like have a series/parallel switch for running in 12 volts or 48 volts. Most important, I would like to have a diagram for just how to wire this up. Jeremy
  12. Math Is Hard

    Why Did Microsoft Alter a Man's Race in Their Polish Ad?

    ruh roh http://www.huffingtonpost.com/2009/08/26/microsofts-ad-in-poland-p_n_269366.html I couldn't resist making an animation from the 2 images. Now if I could just make the heads morph...
  13. L

    PIC16F877, sample coding regarding the use of switch

    Homework Statement I'm learning PIC recently. Below is the coding that i have prepared and the attachment is the connection that I used. My question is, why the 2 LEDs will on immediately once i trigger the PIC? This is because the result is not something that should be coming out. What's...
  14. K

    Transistor Switch for R2R Ladder DAC Circuit

    hey! friends i have to construct a two-ways switch. Can i use a transistor in that case. i means i am constructing a R2R ladder DAC circuit. in that circuit, there is a switch in two ways- originally ground and connect to ref voltage when switch is on. Please suggest me, which device is the...
  15. S

    Using a MOSFET and comparator together as a switch

    Hello all, I was advised to use a MOSFET and a comparator together in a solar charger that I am building to stop the solar panel from charging the batteries when full. Seems logical, right? The only problem is I've never used MOSFETs or comparators, so I'm not really sure how to. I need a...
  16. F

    Voltage source -> Ideal switch -> Resistance = Reactive power

    This is a problem i just can't get my head around. When you have a circuit consisting of a "Ideal Voltage source -> Ideal switch -> Ideal Resistance" all in series. The voltage source produces a sinusodal voltage and the switch is set to cut off a part of any rising curve...
  17. E

    LaTeX Switch From Double to Single Spacing in Latex

    Hello, In writting my thesis, I set the spacing to be double spacing, complying the requirements. But in some paragraphs, I need to make the spacing single spacing, as in the abstract. When I write \singlespacing control sequence just before the intended paragrah, it shows no affect. How to...
  18. DaveC426913

    LED 'ON' light across power switch

    I wish to attach an LED indicator light across the main power to the 12V battery on my boat. This light will let me know from a convenient location whether I've remembered to switch off the main power. How do I wire it up? The LED is obviously 3V. The light would only be ON if the power...
  19. K

    Remote Control Car:H-Bridge Vs Simple Switch DPD

    Hello everybody! I am a beginner in electronics and mechanical but i really want to know more in that field. Now, i want to make a remote control car with a high speed possible. I have already made one with a 3Volts DC MOTOR controlled by a PWM (LM555) and potential-meters, the power supply...
  20. H

    Controlling two lights separately with one switch

    I have a single lighting switch at home which controls two sets of light separately, but I have no idea how it works. Here's what the single switch does when flipped on-and-off quickly, On -> Light A turns on Off -> A turns off On -> Light B turns on Off -> B turns off On -> Light A and...
  21. L

    SCR as a switch control for automatic light dimmer

    Hi guys, can u guys help me on this?? I want to design and construct an automatic light dimmer circuit that controls the energy delivered to a 12V or 24V DC light bulb corresponding to the ambient light intensity. The control of energy will be established through switching action to improve...
  22. L

    Automatic light dimmer using SCR as switch control

    Hi guys, can u guys help me on this?? I want to design and construct an automatic light dimmer circuit that controls the energy delivered to a 12V or 24V DC light bulb corresponding to the ambient light intensity. The control of energy will be established through switching action to improve...
  23. S

    Looking for: Programmable stand alone 120v switch?

    I am a mechatronics engineer and need to find a stand alone 120v 15amp electrical switch that is programmable. I need it to be able to program a sequence of on/offs for specific time intervals for both on and off. The user needs to be able to hit a start button to initiate the programmed on/off...
  24. N

    Is a transistor a switch or an amplifier

    After doing some research, I am still confused is a transistor a switch or an amplifier. If it can be used as a switch how do I find the part that will work with the gate voltage that I give it. mouser.com wasn't really helping me in finding the right part.
  25. Ivan Seeking

    News Sen. Arlen Specter to switch parties

    CNN is just now reporting that Arlen Specter - one of the most senior Republican Senators - will become a Democrat! If Al Franken does assume office for Minnosota, which we expect to happen, that would give the Democrats a fillibuster-proof 60 vote majority in the Senate.
  26. U

    A question with capacitor and a switch

    Homework Statement Initially, the switch is in position A and capacitors and are uncharged. Then the switch is flipped to position B. Afterward, what are the charge on and the potential difference across each capacitor? Position a is a 100V battery and a 15microF capacitor C1. Position B...
  27. A

    Why do the Earth's magnetic poles switch every once in a while?

    My geology prof says that no one knows. I think I'll cry if that's true. It's driving me nuts.
  28. D

    Closing a Switch with Microcontroller: Simple Answer

    I am trying to figure out how to close a simple switch with a microcontroller. Do I need a relay to do this? Please give a simple answer since I don't know much about electronics.
  29. S

    Programs Wanting to switch to unaccredited engineering degree

    My school is accredited and most of it's engineering degrees are accredited by ABET, but the "engineering science" degree is not. I'm currently 2.5 quarters away from finishing an accredited degree, but a class this quarter has me doing so bad (and the instructor isn't worth praising) that I...
  30. H

    Switch Fields After PhD: Strategies for Future Employment

    I have almost completed a PhD in a field of computational materials science. I've kinda lost interest in it, and I'm wondering what are some strategies I can use to move to different areas for future employment ...
  31. D

    What is the potential difference Vad-Vac?

    1. The problem statement The capacitors in the figure are initially uncharged and are connected, as in the diagram, with switch S open. The applied potential difference is Vab = + 210 V. What is the potential difference Vcd? Homework Equations (series) 1/C = 1/c1 + 1/c2 + ...
  32. A

    Double Pole Switch Used After KWH Metre in Homes

    Why is a double pole switch used after the kwh metre in our houses and not a simple s
  33. C

    Programs Considering a Major Change: Exploring Career Options in Engineering and Physics

    Hey guys, I am currently an Engineering Physics student in my sophomore year, however i am having some second thoughts. Basically I am wondering if anyone has had any trouble getting a job with a bachelors in EP or physics? I originally thought i would go onto grad school for astrophysics or...
  34. J

    3-Step Process of a Simple RC Circuit with Battery and an Open Switch

    The following 3 step process refers to a simple RC circuit with a battery and an initially open switch: 1- the switch is closed, allowing the capacitor to charge; 2- after the capacitor has charged, a slab of dielectric material is inserted between the plates of the capacitor and time...
  35. M

    Solving Switch Statement Problem with y as Integer

    Homework Statement switch statements. y is an integer number. Use a switch statement to set B equal to one of the following values: true, false, or the vector [1 0 1]. If y is {1,2,3,5,7}, then set B to true. If y is {4, 6, 8, 10}, then set B to false. If y is neither, then set B to the...
  36. benzun_1999

    How can I effectively short a push button switch using electronics?

    Hello, I have a switch, which is a normal push button switch. It does not latch. I need to design a simple electronics circuit that can be used to short the switch electronically. Any suggestion? I have tried using a transistor switching mechanism but it is not working properly. Any...
  37. DaveC426913

    Circuit testing handheld switch

    Help! I've got this device that I feel responsible for getting working and I want to test its circuits. It is currently dead. It's this http://www.canadiantire.ca/browse/product_detail.jsp?PRODUCT%3C%3Eprd_id=845524443293144&FOLDER%3C%3Efolder_id=1408474396672427&bmUID=1230269280757". The...
  38. T

    A Unit Question: Flicking a Switch

    If I wanted to work out the calculations for flicking a lightswitch, what units am I dealing with when I am determining how hard it is to flick the switch? For example, I am sure that I wouldn't say it takes a certain amount of force because a large force over a short amount of time wouldn't...
  39. T

    NooB Question - 12V wiring switch circuit

    Hello all, I am stuck in a rather simple, yet confusing quandary.. I'm working on designing a light kit for a Honda side x side utility vehicle. We are planning on drawing power from the back of the existing cigarette lighter auxiliary outlet on the instrument panel, and running the power...
  40. S

    Designing a Mosfet Switch for DAQ Simulation

    Hi Guys, I need to design something that will isolate our DAQ (Data Acquisition Card) for a basic simulation we need to do. I was thinking about designing a mosfet switch, where the DAQ sends some voltage to the gate above the threshold voltage to turn the MOSFET on and 0 V to turn it off...
  41. T

    How durable are electromagnetic switches and magnets?

    So, I have an electromagnetic switch. Which works in this way. A rod has 4 magnets attached to the front of it and 4 magnets attached to the back of it. In the center there is the winding. When I apply current to it, the rod moves towards one end and hits a steel plating on that side fixing...
  42. U

    Preparing for a Switch to EE with a Physics Degree?

    I am a 2nd year physics undergrad and I am thinking about a switch to EE. I like the thought of grad school, maybe to be an engineer, so I want to know if my undergrad in physics is going to prepare me enough. Some of the upper year classes I will be taking are: (all 1 term classes): E&M I...
  43. W

    Tensor Indices Switch with Infinitesimals and Space-Time Derivatives

    Wondering if this is valid to do, if I start with the expression \delta\omega^{u}_{ \singlespacing v} x^v \partial_u where \delta\omega is an infinitesimal, and \partial a space-time derivative, is it still valid to drop and raise the u to obtain \delta\omega_{u v} x^v...
  44. M

    2 people in a canoe, switch places, canoe moves, find mass of one person

    Ricardo, mass 80 kg, and Carmelita, who is lighter, are enjoying Lake Merced at dusk in a 20 kg canoe. When the canoe is at rest in the placid water, they exchange seats, which are 3.0 m apart and symmetrically located with respect to the canoe's center. Ricardo notices that the canoe moved 45...
  45. jtbell

    Looks like we'll all have to switch to tablet PCs

    Keyboard sniffers to steal data
  46. J

    Calculate Collector Current w/ Emitter @ 100mA - Transistor Switch

    Homework Statement http://img300.imageshack.us/img300/2640/17569077cy5.jpg The transistor is a N-P-N type. When the siren is functional, the resistance of thermistor is 120 ohm. R1 is 600 ohm. The question is "Calculate the collector current if the emitter current is 100mA". I know that...
  47. T

    Seeking Surge Protection for Switch and Motherboard

    Hi, I have a switch connected to a motherboard. During ESD test with 8000kV (directly on the switch) the ESD spike caused my system to reboot, and I need some kind of surge protection betwee nthe switch and motherboard. I am not sure what I need to look for? Can anyone suggest a...
  48. wolram

    How to Switch Off an Overactive Brain

    I guess all you guys have over active brains, but how do you switch them it off?
  49. N

    Using transistor to switch leds on/off

    I'm currently using this circuit, but without the rectifying portion,a audio source from mp3 player instead of a mic, and a 4V LED instead of a bulb. My power source is 12v. However, the voltage across the LED is only around 1-1.5V. How can i increase the voltage across the LED? Here is what i...
  50. N

    Photovoltaic cell as an on/off switch - circuit help

    Photovoltaic cell as an "on/off" switch - circuit help Hi all, My first post here. I'm a Mechanical Engineer prodding my finger where it shouldn't be - circuits! I need help and I am hoping you folks can. PLEASE excuse the umb terminology - I don't know this world well! I want to turn a...
Back
Top