Resistance Definition and 1000 Threads
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How to calculate the equivalent resistance in this Circuit?
I start from far right: Green and blue are parallel Connection: This in turn is in series connection with black resistor: and so on ... This is what I'm ending up with My final equivalent resistance is (275/17) Ω. Is this correct?- VitaminK
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- Circuit Equivalent Equivalent resistance Resistance
- Replies: 33
- Forum: Introductory Physics Homework Help
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Calculate the current in all parts of this electric circuit
In the circuit below, the output is 23 W across the resistor with the resistance 6 Ohm. Calculate the amount of current in all parts of the circuit as well as the polarity and EMF ε of the unknown battery. Circuit: My attempt: I get 6 unknowns with 5 equations. I don't know how to find the...- Karl Karlsson
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- Circuit Current Electric Electric circuit Electromotive force parts Power Resistance
- Replies: 21
- Forum: Introductory Physics Homework Help
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Help with adding air resistance into my projectile trajectory function
Hey, I am working on a video game in which there will be archers who have the ability to shoot at enemies. My game is two dimensional and I am trying to calculate the angle at which the archer, given an initial velocity, has to shoot in order to hit the target perfectly. I came up with the...- CraterHater
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- Air Air resistance Function Projectile Resistance Trajectory
- Replies: 8
- Forum: Electromagnetism
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Calculate the multiplier resistance
Question: My attempt: So the resistance of the multiplier resistance comes out to be 19.25 ohms?- Bolter
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- Resistance
- Replies: 1
- Forum: Introductory Physics Homework Help
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What is the Correct Value of Multiplier Resistance?
This is the problem itself shown below And this is what I have tried, I get an answer of 29 ohms Would you agree?- Bolter
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- Resistance Value
- Replies: 1
- Forum: Introductory Physics Homework Help
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Putting internal resistance in series with a voltage source
Suppose I have a galvanic cell, where I've arbitrarily set the (-) anode to have a potential of zero volts and the (+) cathode to ##\epsilon## V. The electrodes are connected via the load, but also via the solutions and salt bridge in the centre. Edit: The two trailing wires are connected to a...- etotheipi
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- Internal Internal resistance Resistance Series Source Voltage Voltage source
- Replies: 10
- Forum: Electromagnetism
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Working out the shunt resistance for a galvanometer circuit
Here is the problem I have tried to draw the set up for both cases which the question had described above, and came to these 2 equations. But I can't see how it would help me to work out the resistance of the shunt? Any help would be really great! Thanks- Bolter
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- Circuit Galvanometer Resistance Shunt
- Replies: 7
- Forum: Introductory Physics Homework Help
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Regarding the work done against air resistance
Here is the question: I have correctly calculated the power produced by the thrust force (P = Force x Velocity = 9.0 × 104W) , the work done by the thrust force over 3 minutes (W = Power x Time = 9.0 × 104 × 3.0 × 60 = 1.6 × 107 J) , and the gain in potential energy over this period (mgh =...- vodkasoup
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- Air Air resistance Resistance Work Work done
- Replies: 2
- Forum: Introductory Physics Homework Help
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Finding the resistance of this shunt resistor
How would I go about this question? Here is my attempt at it but I haven't really gone anywhere with this :oldconfused: Any help would be really appreciated!- Bolter
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- Resistance Resistor Shunt
- Replies: 16
- Forum: Introductory Physics Homework Help
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Does the resistance of a material vary when introduced into water?
Suppose we have a copper wire, of resistance R, and we introduce it in water, when applying now a certain potential difference between the two ends, will the intensity that circulates through the wire be the same, and therefore also the resistance ?, is there going to be a potential drop due to...- Cloruro de potasio
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- Material Resistance Water
- Replies: 9
- Forum: Electromagnetism
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Discharging this capacitor in an RC bridge circuit
The voltage source in the circuit below has been switched on for a long time when the switch S switches off. How long will it take before the current coming out of the capacitor has become less than 1 mA? My attempt: I am far from sure that my solution is correct. This is because i...- Karl Karlsson
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- Bridge Capacitor Circuit Discharge Rc Resistance
- Replies: 10
- Forum: Introductory Physics Homework Help
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Engineering Problem with the Thevenin equivalent resistance
Good day I have a problem to find the equivalent resistance from the capacitor point of view the solution says it's R1 but for me we still have R2 and R3 we have not deal with ! many thanks in advance- Amaelle
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- Circuits Equivalent Equivalent resistance Resistance Thevenin Thevenin equivalent
- Replies: 4
- Forum: Engineering and Comp Sci Homework Help
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What's the total amount of resistance in this kind of circuit?
I am not sure how to treat the extra connections K12 and K34. My first guess would be (R1 and R2) are parallel and so are (R3 and R4) and (R5 and R6) ,so R_{total}= {R1*R2} /{R1+R2} +... Or maybe the behaviour is like this: (R1, R3, R5) are in series , and (R2 R4 R6) are, thus R_{total}=...- Reneee
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- Circuit Resistance
- Replies: 4
- Forum: Electrical Engineering
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Engineering Find the output resistance in a amplifier (MOSFET) small-signal model
I have to solve a problem related with an 'invented' (non-real) MOSFET working in its saturation region (amplifier). I have solved all the questions, but I'm unable to get the last one. Basically, I need to determine the output resistance of the amplifier as a function of other given 4...- Martel
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- Amplifier Circuit analysis Electronics engineering Model Mosfet Output Resistance
- Replies: 2
- Forum: Engineering and Comp Sci Homework Help
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Understanding Total Voltage in Parallel Circuits
I really don't have any clue why the total voltage is equal to the voltage drop over the 3 Ω and 2 Ω resistors and independent of the 4 Ω resistor . Does it have to do with parallel circuits?- physics_CD
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- Circuit analysis Homework Resistance Voltage
- Replies: 6
- Forum: Introductory Physics Homework Help
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Wheatstone Bridge: Substitution Resistance Formula Derivation?
Hello, In high school, I had been taught about finding substitution resistance from Wheatstone bridge. The formula: a. If the cross product of ##R1## and ##R3## is same as ##R2## and ##R4##, the galvanometer in the middle (##R_5##) can be omitted and use series-parallel principle to solve for...- bagasme
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- Bridge Dc circuit Derivation Elecricity Formula Resistance Substitution Wheatstone bridge
- Replies: 4
- Forum: Electromagnetism
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Engineering DC bias current and small-signal resistance
We are given that ##i_D = 8\cdot 10^{-12} (e^{v_D/20m} - 1)## Hence ##i_D' = e^{50 v_D}/2500000000## and ##i_D'' = e^{50 v_D}/50000000## Then I have that ##\delta i_D \approx\frac{ e^{50 v_D}}{2500000000} \cdot \delta v_D = \delta v_D / 5## Cancelling ##\delta v_D## from boh sides and solving...- JessicaHelena
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- Bias Current Dc Dc circuit Diode Diode circuit Nonlinear Resistance
- Replies: 3
- Forum: Engineering and Comp Sci Homework Help
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Engineering A circuit with non-linear devices
I honestly don't know how to quite even begin this problem. Looking at Fig 3-2, the slopes of the graphs are 1/R, and hence where the slopes are 0, we have infinite resistance, in which case current wouldn't flow through that resistor and hence simplify the circuit. So I was trying to find...- JessicaHelena
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- Circuit Circuit analysis Current Non-linear Resistance Voltage
- Replies: 5
- Forum: Engineering and Comp Sci Homework Help
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Engineering Finding voltages in a linear circuit
From the circuit I have: ##-v_b + v_a + V = 0## ##v_b - V = v_a## ##i_1 = (v_b - V)/R_1## ##I + i_2 = i_1## ##(v_b - V)/R_1 = I + v_b/R_2## From this last equation I get ##v_b = 10.8## and hence ##v_a = 5.8##. However, apparently that is wrong. (And hence my answers to #2 were all wrong as...- JessicaHelena
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- Circuit Circuit analysis Current Linear Power Resistance Voltage
- Replies: 23
- Forum: Engineering and Comp Sci Homework Help
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Engineering Solving Circuit Equations: A Struggle
I am having a hard time solving this. Letting \$i\$ be the current flowing into ##R_3##, ##i_1## the current flowing through ##R_1## and ##i_2## the current through ##R_1##—and the node between R3 and R1 be e_1; Using KVL and KCL, I've managed to find that ##i + I = i_1 + i_2## Hence...- JessicaHelena
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- Circuit Circuit analysis Dependent source Resistance Thevenin equivalence Voltage
- Replies: 15
- Forum: Engineering and Comp Sci Homework Help
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Deciphering this problem statement: Air resistance on projectiles
I am struggling with our equation and where to plug in my velocities and forces? After looking at my book I don't understand why p(t) would be where I plug in force, and why variable "t" is where we plug our velocity in? When the problem says "what happens if you try to use a polynomial of...- cookiemnstr510510
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- Air Air resistance Projectiles Resistance
- Replies: 7
- Forum: Introductory Physics Homework Help
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Platinum resistance thermometer and Kirchoff's Laws
Hi, I found this question/s online and I was wondering if somebody was able to explain the answer given, specifically the first bit that says R1/(R1+R2) = R4/(R3+R4) (is this something to do with an equivalent resistor to replace the two in series on each side? But why are R1 and R4 the...- penroseandpaper
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- Laws Platinum Resistance Thermometer
- Replies: 1
- Forum: Introductory Physics Homework Help
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Engineering Thevenin resistance and Thevenin voltage confusion
- theycallmevirgo
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- Confusion Resistance Thevenin Voltage
- Replies: 5
- Forum: Engineering and Comp Sci Homework Help
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Can We Design a Tube to Resist Fluid Flow?
Hello everyone, I want to ask something. Can we design a tube that can completely resist the flow of a fluid? Maybe using either viscosity or surface tension approach? Thanks- ramadhankd
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- Flow Fluid Fluid flow Resistance
- Replies: 3
- Forum: Mechanical Engineering
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A Current spreading decreases resistance?
I have a Question to the Independence of the probe distance for a four-probe-measurement technique. In a paper the author is argument that the resistance of a 2D shape is NOT dependent of the distance between the probe which measure the voltage drop, cause he says that the current spreading...- JanSpintronics
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- Current Resistance
- Replies: 9
- Forum: Atomic and Condensed Matter
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Obtaining the series and shunt resistance of a photodiode from the datasheet
Hello, Hello, For a project , i need to modele a photodiode with a current source in paralelle with a shunt resistance and in serie with a resistance to use it in a bigger circuit. The photodiode we will use is SFH7050, the datashhet is provideed here...- louisnach
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- Photodiode Resistance Series Shunt
- Replies: 3
- Forum: Electrical Engineering
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Does Polarity and Current Direction Affect Energy Flow in AC Circuits?
I assume that because there is a resistance, the polarity of the voltage must be the same as the charge flow, and thus the current, in order for energy to flow in the same direction. For instance, could I use the example of a light bulb (the resistor) plugged into AC lines; we know that if the...- charminglystrange
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- Current Electrical Electricity Polarity Resistance Voltage
- Replies: 2
- Forum: Introductory Physics Homework Help
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Modeling a ball thrown vertically including drag from air resistance
So I'm trying to figure out how to model a ball getting thrown vertically with the starting velocity v_0. So I've come up with a differential equation which I'm pretty sure is correct: Where D is a constant. So far so good. My problem is solving this. This is my attempt: And when i do this...- MigMRF
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- Air Air resistance Ball Drag Modeling Resistance
- Replies: 6
- Forum: Electromagnetism
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Electric current and resistance question
Homework Statement:: problem solving You build a wire by combining an 8 inches copper wire with a 10 inches nichrome wire. If their combine resistance is 10 kΩ, find the cross section area of both wires. The nichrome wire has twice the area of the copper wire. Homework Equations:: I = V/R...- Elisapan622
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- Current Current calculation Electric Electric current Resistance Resistance calculation
- Replies: 2
- Forum: Introductory Physics Homework Help
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Electric current and resistace problem
This is a problem I have been strugglying since I don't know if I should work it together or apart I ask my teacher and I don't know if I listened well but he told me to use the combine resistance and substract it with the restistance of the material. You build a wire by combining an 8 inches...- Elisapan622
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- Electric current Resistance Resistance calculation
- Replies: 1
- Forum: New Member Introductions
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Introductory Circuit Analysis—power ratings
I am going through "Circuit Analysis for Dummies". On pg 18, it says, "If you calculate the power dissipated as 0.1 watts, then a 0.25-watt resistor can handle this amount of power. A 0.125-watt resistor should be able to handle that amount as well, but when it comes to power ratings, err on the...- JessicaHelena
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- Circuit Circuit analysis Current Introductory Power Resistance
- Replies: 6
- Forum: Electrical Engineering
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What is the resistance of the bulb filament
i don't know where to start- isay1224
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- Bulb Filament Resistance
- Replies: 3
- Forum: Introductory Physics Homework Help
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Engineering Find the unknown resistance in this series circuit
How i can find r2 value in this circuit? R1 = 2 R3 = 5 E = 20v- ahmed elshimy
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- Circuit Resistance Series Series circuit
- Replies: 7
- Forum: Engineering and Comp Sci Homework Help
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Determine the effective current value in the circuit with C and R
Given: U = 220 V f = 50 Hz r = 20 Ohm C = 100 μF Find: I Solution: 1) Xc = 1/(ω*C) = 1/(2*π*f*C) = 1/(2*π*50*10^-4) = 31.83 Ohm 2) R_eq - equivalent resistance R_eq = (r*Xc)/(r+Xc) = (20*31.83)/(20+31.83) = 12.28 Ohm 3) I = U/R_eq = 220/12.28 = 17.9 A True answer given in the textbook is 13 A...- Leonid92
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- Alternating current Capacitor Circuit Current Resistance Value Voltage
- Replies: 3
- Forum: Introductory Physics Homework Help
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"Heat resistance temperature" and melting point?
I've got a kitchen bowl made of polypropylene, it states that the "heat resistance temperature is 90 degree cel", while on Google, I found that the melting point of PP is 160 degree cel. I understand that melting point is the temperature in which the atoms/molecules change its state from solid... -
Corrosion resistance of 6105-T5 anodized aluminum for wastewater?
Hello, I'm looking for structural materials that will act as the frame (skeleton) for the housing surrounding a waste container. The frame will structurally support HDPE panels as walls. This will be above ground for use in Uganda (but we can ship materials), under a raised squat toilet hole...- hjannett
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- Aluminum Corrosion Resistance
- Replies: 2
- Forum: Materials and Chemical Engineering
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Find the time when the projectile runs into the hill (with air resistance)
vy=vter + (vy0 -vter) e-th/τ where tau=m/b EQ 1 Okay, for part a, I used Eq 1 I let vy=vy(th)=0 --->The reasoning is that the projectile would stop moving for a short time when it hits the incline, but I have a feeling that reasoning is faulty I let vy0=v0sinθ Then the equation became...- Moolisa
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- Air Air resistance Hill Projectile Resistance Time
- Replies: 6
- Forum: Introductory Physics Homework Help
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Engineering I can't determine the capacitive and inductive resistance of the circuit
Hi, I'm trying to solve this but it becomes difficult. I'm using KCL and I repalce ZL = j0,1ω (Ω) , ZC=... etc. Finding 3 equations with 3 unknown variables (plus the ω). And now is the time for Cramer's rule. I'm not sure if I should move on. What do you say ? I'm on track ? Thanks. ..- Michael_0039
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- Circuit Circuit analysis Kcl Resistance
- Replies: 8
- Forum: Engineering and Comp Sci Homework Help
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How to find the equivalent resistance of this electric circuit?
Summary: How to find equivalent resistance of the electric circuit? I need to solve the following problem: Calculate equivalent resistance of the circuit (figure1), if all six resistances are the same: r1 = r2 = r3 = r4 = r5 = r6 = 100 Ohm. True answer: 66.6 Ohm. I tried to solve this...- Leonid92
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- Circuit Electric Electric circuit Equivalent Equivalent resistance Resistance
- Replies: 5
- Forum: Engineering and Comp Sci Homework Help
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Parallel circuit with internal resistance
4 resistors R1= 10 Ohm R2= 7 Ohm R3= 6 Ohm R4 = 18 Ohm, internal resistance of source is 0,5 Ohm and supply voltage is 27V Total resistance in parallel resistors 1/R = 0.465 taking the inverse of that i get 2,15 Ohm. Add to that the internal 0,5 and the total comes out to 2,65 Ohm. Total...- dbag123
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- Circuit Internal Internal resistance Parallel Parallel circuit Resistance
- Replies: 6
- Forum: Introductory Physics Homework Help
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Finding Equivalent Resistance, Current, and Voltage across a resistor
- rugerts
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- Current Equivalent Equivalent resistance Resistance Resistor Voltage
- Replies: 4
- Forum: Introductory Physics Homework Help
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Maximum power in this resistor circuit
My attempt-: So the resistance is coming to be negative.Can anyone tell me my mistake.Thanks.- Physics lover
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- Circuit Maximum Maximum power Power Resistance Resistor
- Replies: 7
- Forum: Introductory Physics Homework Help
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Resistance of composite material
Composite materials consist of various components such as moist wood ,how will the internal resistance of this material behave? If I want to study the resistance of composite materials, which topic should I study?- Another
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- Composite Material Resistance Resistance calculation
- Replies: 1
- Forum: Electromagnetism
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Green's function and the resistance across a Hypercube
Homework Statement: I do know how to solve the resistance network problem in two dimensions. However, in this problem they want it in 3 dimensions and higher and I don't know how to do that Homework Equations: - In the picture you can see the solution to the two dimensional version- Hamsi
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- 4th dimension Function Green function Green's function Higher dimensions Resistance
- Replies: 3
- Forum: Introductory Physics Homework Help
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Wear Resistance: AISI 1074/75 VERSUS 304 2B Annealed Stainless
Can anyone here tell me which of these two materials would have a greater resistance to wear? I understand that higher carbon content generates greater hardness, which provides relatively higher wear resistance. And alloying can increase wear resistance -- but I'm not sure how to directly...- JohnM77
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- Resistance
- Replies: 3
- Forum: Materials and Chemical Engineering
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Resistance and Precession Torque of a Gyroscope
Hi, Say there's a gyroscope with moments of inertia Ix, Iy and Iz spinning around a vertical z-axis (see attached illustration) with a given angular velocity ωz. Notice that the gyroscope is floating in space as in that there's no gravity acting on the gyroscope. Now I apply a torque τx...- dishwasher95
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- Gyroscope Precession Resistance Torque
- Replies: 11
- Forum: Electromagnetism
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Resistance of Platinum decreases with an increase in temperature ?
Basic Procedure The experiment basically involves finding the null point on the Carey Foster's bridge with the PRT as the unknown resistance and using a Resistance box as the variable resistance. In the above diagram, P and Q are 2 fixed resistors of equal resistances. For obtaining the first...- TachyonLord
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- increase Platinum Resistance Temperature Thermal physics
- Replies: 2
- Forum: Electromagnetism
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Determining Resistance of a Copper Wire Without Knowing Its Resistivity
What i did is: ##R=\rho\frac{l}{\Sigma}=\rho\frac{l}{d_2^2\pi-d_1^2\pi}## The problem is that I don't have ##\rho##. Is there a way to find ##R## without knowing it? Many thanks.- Archimedess
- Thread
- Copper Copper wire Resistance Wire
- Replies: 4
- Forum: Introductory Physics Homework Help
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Thermal Resistance of a Hollow Circular Cone
We can write our radius as a function of the height, z, of our cone: $$R(z) = \frac{R_2 - R_1}{h} z + R_1$$ Where h is the height of our cone, ##h = \frac{L}{40}##. Our cross sectional area, $$A = 2 \pi R t$$ can then be written as $$A = 2 \pi t [\frac{R_2 - R_1}{h} z + R_1]$$ This I am all...- alex_amvdor
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- Circular Cone Resistance Thermal Thermal resistance
- Replies: 9
- Forum: Advanced Physics Homework Help
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Zero Friction on the Moon: Driving at Constant Velocity Without Air Resistance
Suppose we are driving on moon (I mean there is not air resistance) at a constant velocity. Suddenly the car goes on an icy land (the friction is zero). What happens? In other words, if we drive at constant velocity and there isn't air resistance, Is there any friction force between tires and...