Resistance Definition and 1000 Threads

The French Resistance (French: La Résistance) was a collection of French movements that fought against the Nazi German occupation of France and the collaborationist Vichy régime during the Second World War. Resistance cells were small groups of armed men and women (called the Maquis in rural areas) who, in addition to their guerrilla warfare activities, were also publishers of underground newspapers, providers of first-hand intelligence information, and maintainers of escape networks that helped Allied soldiers and airmen trapped behind enemy lines. The Resistance's men and women came from all economic levels and political leanings of French society, including émigrés, academics, students, aristocrats, conservative Roman Catholics (including priests and nuns), Protestants, Jews, Muslims, liberals, anarchists, and communists.
The French Resistance played a significant role in facilitating the Allies' rapid advance through France following the invasion of Normandy on 6 June 1944. The French Resistance provided military intelligence on the German defences known as the Atlantic Wall and on Wehrmacht deployments and orders of battle for the lesser-known invasion of Provence on 15 August. The Resistance also planned, coordinated, and executed sabotage acts on the Nazi electrical power grid, transport facilities, and telecommunications networks. The Resistance's work was politically and morally important to France both during the German occupation and decades that followed. It provided the country with an inspiring example of the patriotic fulfilment of a national imperative countering an existential threat to French nationhood. The actions of the Resistance stood in marked contrast to the collaborationism of the Vichy régime.After the Allied landings in Normandy and Provence, the paramilitary components of the Resistance were organized more formally, into a hierarchy of operational units known, collectively, as the French Forces of the Interior (FFI). Estimated at 100,000 fighters in June 1944, the FFI grew rapidly and reached approximately 400,000 by October. Although the amalgamation of the FFI was, in some cases, fraught with political difficulties, it was ultimately successful, and it allowed France to rebuild the fourth-largest army in the European theatre (1.2 million men) by VE Day in May 1945.

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  1. R

    Resistance equivalence and circuit current

    Homework Statement a) find the equivalent resistance of the circuit below b) each current in the circuit c) the potential difference across each resistor d the power dissipated by each resistor. Homework Equations V=IR R=(1/R)^-1 The Attempt at a Solution Not sure if I did the resistance...
  2. mattbeatlefreak

    Rank Resistors by Energy Dissipation: 5Ω > 10Ω > 20Ω > 90Ω

    Homework Statement Rank the resistors according to to the rate at which energy is dissipated in them. Homework Equations P = I2R P = V2/R Iin=Iout at a node The Attempt at a Solution First I looked considered the 20 Ω (top) and the 10 Ω(bottom). The current in them would be the same, so...
  3. soothsayer

    Calculating thermal resistance across a metal flange

    I've been using the following equation for thermal resistance to make basic calculations for a few different engineering designs: $$R_t = \frac{L}{kA} $$ Where L is the resistance path length, A is the cross-sectional area perpendicular to this path and k is the thermal conductivity of the...
  4. Z

    Calculating voltmeter resistance in DC circuit

    Homework Statement initial problem: A 228 −Ω resistor and a 586 −Ω resistor are connected in series across a 90.0−V line. A voltmeter connected across the 228 −Ω resistor reads 24.0 V . Find the voltmeter resistance. For Req, i got Req=228R/(2+228), R being the resistance of the voltmeter. But...
  5. LtIvan

    Transistor Resistance: Find Current & Formula

    Do transistors give a certain resistance? If so how do you find this resistance? Say Hypothetically for the following example. Refer to (fig.1). The resistor's value is 100Ω, source is 3V. Say if the transistor wasn't there, the amp would be 0.03A or 30mA. But when I run this in a simulation...
  6. PhysicsBoyMan

    Find resistance of resistor connected in series

    Homework Statement Two 1.80 V batteries—with their positive terminals in the same direction—are inserted in series into the barrel of a flashlight. One battery has an internal resistance of R1 = 0.280Ω, the other an internal resistance of R2 = 0.155Ω. When the switch is closed, a current of...
  7. PhysicsBoyMan

    How does emf relate to current, elec potential, & resistance

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  8. S

    The resistance of electrolycra

    I was shown electrolycra recently and initially as you stretch it the resistance increases, which I think is due to the silver in the lycra not being able to shortcircuit as the lycra separates out. However if you keep stretching the electrolycra eventually you reach a critical point at which...
  9. D

    Thermodynamics: Calculating total resistance of window

    Homework Statement A triple glazed window consists of 3 clear glass panes of 3 mm thickness each, separated by air cavities of 12 mm each. The window area is 1.0 m2 . If the thermal conductivity of the glass panes is 0.8 W•m-1•K-1 and of the air cavities is 0.028 W•m-1•K-1 what is the total...
  10. mattbeatlefreak

    Internal Resistance in a Battery

    Homework Statement Three resistors are connected in series to a battery. The resistances are R1 = 15 Ω ,R2 = 25 Ω , and R3 = 30 Ω and the current through the 15-Ω, resistor is 2.7 A . What is the potential difference across the battery terminals if the battery is ideal? What is the potential...
  11. nothing909

    Adding resistance and finding current in each branch

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  12. C

    Extremely low on resistance LDR?

    I need a variable AC attenuator and the only thing I can think of is an LDR. However I would need the on resistance to be very low, less than 10 ohms. I've only found LDRs with on resistances of 100ohms minimum. Is it possible to go lower than the listed minimum is I use a really really bright...
  13. B

    Solution to series resistance function

    Hi, I cannot solve for the function g(t) (eq. 6) in the attached figure where there are two series resistances. My solution is incomplete. I do not know how to use Vx in this solution, which is needed because it contains h(t) found in the solution.
  14. N

    Quantifying Inertial Resistance

    Hi! I am having a little trouble with a question asked by a colleague. There’s a ball B with a certain mass M, at rest. A small ball A of mass m is moving with speed v toward M. If m=M, and the collision is perfectly elastic and the two objects perfectly rigid, than we know that A would come...
  15. D

    Using conservation of angular momentum as a braking system

    Hello, I have a question about using the properties of conservation of angular momentum to provide mechanical resistance. Basically, I'd like to create a device that spins a disk similar to a gyroscope. The device has an external input that, depending on the configured orientation of the disk...
  16. M

    What is the relationship between resistors in a circuit?

    Homework Statement I'm having trouble trying to find equivalent resistance. Here's a picture of some circuits I am trying to simplify (http://puu.sh/ngjMC/38160c3464.png) For example, in circuit a, I can see that the 84 ohm and 105 ohm resistor are in series, and that can be simplified, but...
  17. rkum99

    Can you help decipher this circuit and calculate the voltage?

    Homework Statement [/B] https://wcl.unr.edu/bbcswebdav/pid-634340-dt-content-rid-2875167_1/xid-2875167_1 So I am given the above image, and I am told to calculate the voltage in the circuit. Homework Equations V = IR R_net = (1/R_1 + 1/R_2 + ... + 1/R_n)^-1 for parallel resistors 3. The...
  18. S

    Calculate Resistance and resistivity

    I have voltage, diameter, area, and inverse area data values. How could I calculate the resistance and resistivity with these numbers? I am pretty sure resistance is R=V/I and resistivity= RA/L , so I am not sure how I can calculate resistance without an I value.
  19. C

    Adjust supply voltage based on divider resistance

    Hello, I'm working on a project and I need some assistance. I need to adjust the negative supply voltage to an integrator opamp that I use for DC offset control based upon the resistance in a voltage divider elsewhere in the design. R12 is the trimmer resistor to adjust the CVS circuit and V5...
  20. R

    Microscopic Ohm's Law: Point-Dependent Resistance?

    The microscopic Ohm's law is: J = sigma * E So the density in every point is proportional to the electric field in that point. My question. This sigma is also point-dependent? So the resistor could be made of different materials and ohm's law would hold for every point differently. Or is this...
  21. Brian T

    Determining resistance for unknown circuit

    Homework Statement This was an experiment we did in my lab. You're given a black box with four resistors inside, with resistances 20, 51, 100, and 200 ( k\Omega). The box has three plugs on it, labeled A, B, and C. You take your multimeter and plug into two jacks at a time and measure the...
  22. M

    Would this work to decrease air resistance in sports cars?

    Okay so here is my idea, not really sure how well (if at all) it would work but I am wondering if it would be possible (assuming battery technology is good enough) to ionise air in front of a formula 1 car (or plane or whatever) giving it a charge (like the way lightning works) , then creating...
  23. O

    What's the equivalent resistance between point A and B?

    Simple as that, I've uploaded the image. I don't really care about the exact value, I would prefer just to know the method. So how would I find the equivalent resistance between A and B? Note the component in the middle is a constant current source.
  24. P

    Calculating impact resistance of a silicone wafer

    Wondering the best way to go about calculating the ability of a silicone wafer to withstand impact. Wanting to possibly use a small pc as a fracture barrier to indicate that a part was dropped and may potentially be damaged. Need it to handle 20G. Alternative mat'l suggestions would be...
  25. A

    Find the equivalent resistance between AB

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  26. P

    Find the resistance at 50 degrees C given resistance at 0 C

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  27. A

    Find the resistance of a resistor using Ohm's Law?

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  28. P

    Difference between lights connected in series and parallel

    Homework Statement When two same lamps are connected with the same battery. Their lighting will be greater when they are connected in series or parallel? Homework Equations Series U=U1+U2+U3+... I=I1=I2=I3... Parallel U=U1=U2=U3... I=I1+I2+I3+... The Attempt at a Solution The answer is when...
  29. P

    Find the resistance of a wire (conductor)

    Homework Statement If the diameter of a wire (conductor) is dimidiated , then its resistance: A Remains unchangable B is diminiated C Becomes two times greater D Becomes 4 times greater Homework Equations R=constant*length/Surface The Attempt at a Solution Cross sectional area=pi r^2=pi...
  30. P

    The resistance of a wire (conductor) in cylindrical form is:

    Homework Statement The resistance of a wire (conductor) in cylindrical form is: A Disproportional with the length of the wire (conductor) B Disproportional with the square of the wire (conductor) section C Proportional with the square of the length of the wire (conductor) D Proportional with...
  31. Rumplestiltskin

    Work done by friction (rolling resistance)

    Homework Statement The carriage and its passengers start at rest at A. At B, the bottom of the ride, the maximum speed of the carriage is 20ms-1. The vertical distance between A and B is 110m. The length of the track between A and B is 510m. The mass of the carriage and the passengers is...
  32. CheesyPeeps

    Resistance in Parallel Equation

    The formula to find the total resistance in a parallel circuit is 1/R=1/R1+1/R2+1/R3, but wouldn't it be easier to use R=1/(1/R1+1/R2+1/R3)? I've only ever seen the equation written like that once before, and I'm wondering if there's a reason as to why it's never really used?
  33. kostoglotov

    How conductors/resistors affect electric fields?

    Disclaimer: I'm not sure if this is the correct forum. An ideal conductor (ideal = no resistance) is essentially taking the electric field at one terminal and connecting it to the other terminal. Charge moves when it is in an electric field, electric field strength is in Volts per meter, or...
  34. Likith D

    Does the Current Stay Constant in Series Resistors Connected to an Insulator?

    I was told that for resistors connected in series (whatever the equivalent resistance be) the current flowing through a circuit will be a constant Say i had 'n' number of resistors in series connected to say a battery such that the equivalent resistance was equal to that of an insulator, would i...
  35. P

    Calculate thermal resistance of heatsink required

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  36. kostoglotov

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    Speaking just of long straight wires, not loops, coils or solenoids. Ideal wires have no resistance. Of course they would have no capacitance. And real wires have some very small amount of inductance, no? Firstly, would an ideal wire have some ideal nonzero inductance? Why/why not? After all...
  37. P

    Find emf and the inner resistor of the battery

    Homework Statement When the resistor is R1, in the circle there is the intensity I1 and when the resistor is R2, the intensity becomes I2.Find emf and the inner resistance.[/B] Homework Equations I=emf/R+r The Attempt at a Solution I1=efm/R1+r I2=efm/R2+r efm is equal I1*(R1+r)=I2(R2+r)...
  38. P

    Find the internal series resistance of the battery

    Homework Statement A battery is connected with a resistor R1=4 om and then it is replaced with the resistance 9 om. In both cases the heat released in the same time is the same. Find the inner resistor of the battery. Homework Equations Q=UIt (U-tension; I-intensity, t-time) I=e.m.f/R+r The...
  39. D

    Why energy is lost in capacitor if wires have no resistance?

    The question in textbook:- A 4uF capacitor is charged by connecting it to 200V supply.It is then connected to an uncharged 2uF capacitor.How much electrostatic energy of the first capacitor is lost in form of heat and electromagnetic radiation? My question is that why the energy must be lost...
  40. JordanHood

    Maximum power from a battery with source resistance

    Homework Statement A 5V battery rated at 1800mAh has a soucre resistance of 10 Ohms. What is the maximum power that can be extracted from the battery? Homework EquationsThe Attempt at a Solution I understand that had the battery not had any source resistance then the power out would have been...
  41. Julian102

    How to calculate the equivalent resistance using wye delta ?

    Homework Statement https://z-1-scontent-sin1-1.xx.fbcdn.net/hphotos-xtf1/v/t34.0-12/12435980_942112312550457_1708451532_n.jpg?oh=b29a5e9b2ff96bbf0e11932d081eb25e&oe=568A9B79 [/B] We need to find the equivalent resistance along A to B ie AB Homework Equations R=(1/R1 + 1/R2+...+1/Rn)^-1 ...
  42. needing

    Carburettor throttle slide material

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  43. n.easwaranand

    Zener diode : Calculating the series resistance

    Homework Statement : [/B] Given a voltage regulator with 6.8V Zener diode, input voltage range of 15-20V and load current range 5mA-20mA. Calculate the series resistance R for the regulator.Homework Equations : [/B] Applying KVL and no load situation, we get R = (V - Vz)/Iz where V is the...
  44. N

    2000 kg boat, motor force of 6000 N, resistance 2000 N

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  45. Ryaners

    Python Using Python to calculate projectile motion with resistance

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  46. Azaxa

    Transmission Line Model (TLM) End Resistance (Re)

    Hi guys. I'm looking into the modelling of a transmission line model (TLM) and feel that I'm understanding it fairly well. Although, one parameter keeps popping up with very little explanation as to what it actually is. It seems that to characterize contact resistance for a e.g. GaAs TLM with...
  47. faradayscat

    What is the equivalent resistance from A to B?

    Homework Statement R = 10 Ohms Homework Equations Req = (1/R1 + 1/R2 + ... )(-1) Req = R1 + R2 + ... The Attempt at a Solution I honestly don't even know where to start... The obvious thing to do is 4R + 2R = 6R That's pretty much all I can come up with that makes sense... Any help?
  48. N

    Why did they use only meter resistance for tau of inductor

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  49. Azaxa

    Transmission Line Model (TLM) End Resistance (Re)

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  50. I

    Why does vacuum have resistance?

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