What is Resistance: Definition and 1000 Discussions
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.
Homework Statement
The problem and its solution are attached.
Homework Equations
"Steps to follow for Thevenin’s Theorem:
(1) Find the Thevenin source voltage by removing the load resistor from the original circuit and calculating voltage across the open connection points where the load...
Is ohmic resistance a "necessary evil" in order for transistors to be able to function as logic gates?
I mean, I have seen some circuits for the NAND gate in RTL and TTL and they both seem to involve ohmic resistances. Can we make a super conducting NAND gate that will have total ohmic...
Homework Statement
This graph was given, which describes the current through a resistor, as a function of the voltage.
Then, we were supposed to find the resistance of the resistor when 3V<V<5V.
But it changes throughout this range, doesn't it? Because in the answers (Mind you, this is the...
Homework Statement
Find the combined resistance once the switch is closed.
Homework Equations
V=IR
The Attempt at a Solution
I tried applying Kirchoff’s law but I got many equations, I am sure there is a more efficient way. I also tried to re-draw the circuit, but wasn't sure how to do so...
Homework Statement
translation ; we know the values of
R1 = 1 ohm
R2= 2 ohm
R3= 6 ohm
R4= 2 ohm
R5= 4 ohm
R6= 4 ohm
we can also see the voltmeter reading a potential difference value of 8 volts , and the...
Hello all, I want to say thank you in advance for any and all advice on my question. My classical mechanics textbook (Marion Thornton) has been taking me through motion for a particle with retarding forces.
The example it keeps giving is:
m dv/dt = -kmv
which can be solved for:
v = v0e-kt...
Homework Statement
I came across a question asking " which one of these circuits has the largest resistance to the current?
Homework EquationsThe Attempt at a Solution
* In A the positive terminal of the battery is connected to the p-type region and the negative one to the n-type region...
I"ve seen several texts that say something like this:
Our equation of motion along x is
dvx/dt = -g(vx/vt)
Integrating this, we obtain equation 178 at this link (pretty near the top; sorry, but I can't figure out how to put the equation here). It's from FitzPatrick's online notes for...
I was getting a bit confused with Ohm's law, and the relationship between the current, resistance and voltage/potential difference?
From my understanding, current and voltage both increase or decrease together, while current and resistance do the opposite?
I was then wondering if there was any...
I'm not really sure if this is even scientific but while calculating how much energy is stored in electromagnetic coils and capacitors, pretty much the same formula is used:
For electromagnetic coils it's U=0.5LI2
For capacitors it's U=0.5CV2
Why I think they're the same is that in a sense L to...
Homework Statement
When the defibrillation shock is applied, the capacitor discharges through the patient as shown in the diagram below:
The fraction of charge remaining on the capacitor 1.00 ms after it begins discharging is 0.300.
Calculate the resistance of the patient. Note: This will...
Complete question:
Will flow ever reverse or stop if we increase resistance in this pipe scenario?
There are 2 comunicating vessels. The highest vessel is coninuosly alimented with new water. Water in excess flows down on the sides.
Water will try to reach the same height in both vessels, so...
Homework Statement
https://imgur.com/a/XD3Km4t
I'm trying to find the thevenin equivalent resistance across the opened terminals.
Homework Equations
I know you short circuit the voltage source and do simple circuit analysis, however I'm getting confused in determining what resistors are...
Hello,
I am currently doing research on the aerodynamic properties of a rotating cylinder in a cylindrical housing.
The cylinder represents a rotor in a electric motor. The air gap between rotor and stator is about 0.5mm.
I'm looking for a theoretical analysis and calculation on the...
Homework Statement
I'm asked to find a combination of resistors (parallel and/or series) that uses resistors of 25 Ω, 100 Ω, 50 Ω, and 50 Ω. They should add up to give a total resistance of 62.5 Ω.
Homework Equations
Req for parallel = 1/R1 + 1/R2 + ...
Req for series = R1 + R2 + ...
The...
Homework Statement
I'm asked to find the voltage, current, and resistance through each resistor in the given circuit.
Homework Equations
Req for parallel = 1/R1 + 1/R2 + ...
Req for series = R1 + R2 + ...
The Attempt at a Solution
First, I want to find the total resistance in the circuit...
Homework Statement
Homework Equations
ρl = RA
A = π r2
The Attempt at a Solution
l = RA (ρ is constant)
A1 = π (D/2)2
= (πD2)/4
A2 =π (2D/2)2
= πD2
= A1 /4
l2 = 2*l1
##R=\frac{l}{A}##
R2 = (2l1)/(A1/4)
= 8 l /A
= 8R1
Could someone tell me where is my mistake ?
Homework Statement
Calculate the magnitudes and directions of the currents in each of the 3 resistors in the circuit above, if...
(a) ...both batteries have zero internal resistance.
(b) ...each battery has an internal resistance of 1.0 Ω.
Homework Equations
I1 = I2 + I3 (Node Law)The...
< Mentor Note -- thread moved to HH from the technical forums, so no HH Template is shown >
a) Using the Yenka (or similar) simulator, you are required to build an RS flip-flop using 2 NAND gates, switches, LEDs and 330Ω resistors. Test the circuit and prove its correct operation against the...
Homework Statement
Homework EquationsThe Attempt at a Solution
From symmetry , C and D are at the same potential . So , resistance between them can be removed . This leaves us with three parallel branches between A and B i.e 45 Ω || 45 Ω || 15Ω .
The net resistance will be 9 Ω .
But this...
Homework Statement
Three identical batteries are first connected in parallel to a resistor. The power dissipated by the resistor is measured to be P. After that, the batteries are connected to the same resistor in series and the dissipated power is measured to be 4P (four times larger than for...
I'm currently developing a heat sink for a product that produces up to 150 W max power dissipation. I'm currently getting a negative thermal resistance for the heat sink. I don't think that is possible..
I'm not sure how to move on at this point to properly design a heat sink to meet the heat...
I'm currently doing a heat sink calculation design and having a little confused moment with the area of the chip with a AuSn (Gold Tin Solder) pre-cut that's attached to the bottom of the chip.
I've tried looking around online for AuSn's thermal resistance value, but there is none besides a...
Homework Statement
Consider the electric circuit shown in the figure. Assume that V = 13.7 V, R1 = R2 = R3 = R4 = R5 = 7.00 Ω. What is the equivalent resistance of the circuit?
Homework Equations
total voltage of a series circuit is the sum of the voltage of all the resistors
total current of...
Homework Statement
A coaxial cable consists of a core cylindrical wire and a coaxial cylindrical shell, as illustrated in the Figure below. Consider a cable made of copper, which has resistivity of
ρ=1.70×10−8Ω·m. Thecorewirehasaradiusof r =1.0mm. Theinnerradiusofthe 1
outer shell is r = 5.0...
Homework Statement
Coaxial cable has radius a of copper core and radius b of copper shield. Between there is an isolator with specific resistance ζ. What is the resistance of this cable with length L between the core and the shield?
Homework Equations
First, I tried to solve this like this...
A circuit contains a 7.5V d.c power supply and three resistors. The total resistance of the circuit is 30 ohms. Why will the largest current in the 18 ohm resistor? As far as I know is that the smallest current will be in 60 ohm resistor because it has the maximum resistance. Please explain...
Hi! I'm working on a project in which a small microcontroller with a max. analog input of 5v takes readings from multiple sensors. I would like to make this input window a bit more versatile, and turned to voltage dividers as a solution. 'Problem is, I'm having a bit of trouble understanding how...
Hi everyone,
I was wondering how to best calculate the breakage resistance of a drill hole which is being flowed through with a certain volumetric throughput within a polycarbonate (PC) rectangular plate. Well basically, the breakage resistance of the PC around the drill hole :)
The plate is...
Homework Statement
I need to calculate the specific conductivity k and the resistance R of a cell containitng 0.01 M HCl and 0.1 M acetic acid (HAc).
I know the molar conductivity of HAc: Λm = k/c = 5.14 cm2S/mol.
I also know Ka (HAc) = 1.795 *10-5.
I know the cell constant Kcell = R*k =...
Homework Statement
Homework EquationsThe Attempt at a Solution
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The circuit is symmetric about AC and BD , but I am not sure how to use this to simplify the circuit .
Could someone help me in solving this circuit using symmetry considerations .
Homework Statement
Homework EquationsThe Attempt at a Solution
I am trying to solve this question by symmetry .If I draw a line perpendicular to the line joining AB then points C and D are symmetric . Now I am unsure how to proceed further .
Dears,
Please help me out with this. The attached figure is an equivalent circuit of an induction machine. I'm trying to find the current (Is). It's assumed that the core losses are neglected and hence Rc =0. If this is the case, then Rc (short-circuited) is in parallel with jXm. What's the...
I recently made a flashlight/ laser pointer that can charge my phone, and I was wondering as to how I could make it resistant to the rain while allowing the top to be removable to switch out the batteries and make repairs. I also plan on making it attach to my arm like a gauntlet. So how could I...
Homework Statement
Homework EquationsThe Attempt at a Solution
I will call the topmost node T , middle node M , bottommost left node L and bottommost right node Q .
I tried to use symmetry arguments . If I connect a battery across AB , i1 flows through branch AT , i2 through AM , i3...
I placed a hot metal lid on a cool surface. When i tried to pull it up, it had a lot of resistance, i had to really try to pull it up. I could hear sounds under the lid, I'm guessing it was boiling water.
What do you think could have caused this resistance?
Homework Statement
A metal rod can slide on a rail without any friction in the presence of uniform magnetic field of B=1T which is perpendicular to the plane of the paper.The distance between the tracks is d=0.1m and the resistance given is R=0.1 ohm.The resistance of the rail is negligible and...
What is wrong here. If I double speed drag will be 4 times higher. The engine needs to put out approximately 4 times more power. Energy consumption will be 4 time higher for a specific time period. However if it is a fixed distance I will arrive in half the time an the energy consumption will...
Hello everyone
I was hoping you could help me with something, in my analog electronics course..
In the diagram below, is displayed a circuit and its equivalent...
I don't understand why the input resistance is only the parallel combination of R1 and R2??
Why doesn't Rsi contribute to the...
Hello!
Why does resistance to acceleration depend on both the velocity of the object as well as the direction of the force?
In circular motion, we can measure the centripetal force and centripetal acceleration, then we can calculate objects mass. Speed remains constant.
But we would get the...
Homework Statement
Homework Equations
Equations posted in pictures attached
The Attempt at a Solution
I haven't attempted it yet because I am confused about something. If the-cv^2 case is for objects that hit terminal velocity at the fastest rate, why are my graphs showing that I should use...
Homework Statement
decreasing the resistance increases the current if the voltage remains unchanged.
Homework Equations
V=IR
The Attempt at a Solution
The solution in the book does not count this as a true statement, but it seems true to me. Is there any reason why the statement would be false?
Hi, we have done an experiment where we have to measure the resistance of a sample of Ge doping-p and how it changes due to a magnetic field perpendicular to the sample with a costant current.
We have found that R(B) has a quadratic trend (we have fit the dates with y = a[1+b*B^2] with a and b...
I have found research from multiple sources and probably shouldn't question but I want to be clear.
Inside a generator you have a fixed number of poles and a fixed number of induction coils, the particulars are not important. As a pole rotates past the "inductor" which holds the coil there...
Hello,
I came across this line in my textbook:
"Total peripheral resistance (TPR) increases diastolic pressure more than systolic pressure."
I don't understand how the peripheral resistance would increase the diastolic pressure more than the systolic pressure?
Could some one explain that...
Homework Statement
if someone could help me with this it would be much appreciated. In physics, I used a 98Ω resistor in a series circuit and measured the current and voltage output from battery, using the current and voltage I calculated the resistance. I=0.0094A V=1 Rt=1/0.0094=106.38Ω even...
Homework Statement
Homework Equations
-
The Attempt at a Solution
I tried to break it down to:
But apparently it is incorrect, can someone tell me the correct configuration? And explain too! Thanks :)
(Please do not give ambiguous "hints").
Homework Statement
https://imgur.com/3H3pCkD
R is the resistance of each resistor, determine total resistance in the circuit. (see the image in the link above)
Homework Equations
R=1/R₁+1/R₂+1/R₃+... (in parralel circuit)
R=R₁+R₂+R₃... (in series circuit)The Attempt at a Solution
I'm...