Resistance Definition and 1000 Threads

Homework Statement [/B] I'm going exercises and I understand that if the circuit is short circuited that R=10 ohm is 0. (Trying to find Thevelin R in all of these btw) But then I ran across this one where when it's short circuited, isc is found using the current divider principle and it's...

Homework Statement Find the Thévenin resistance for each of the circuits shown by zeroing the sources. Homework EquationsThe Attempt at a Solution I replaced the current source with an open circuit and I'm left with a wye formation but I don't know how to calculate the equivalent resistance

Homework Statement Homework Equations V = I.R The Attempt at a Solution 6 ohm and 3 ohm are series = b Then b pararel to 9ohm = c = total resistance b = 9ohm c = 9/2 ohm I = V/R I = 9.6/c I = 2,13 A Can you help me? Is it right? My friend's answer is 0,8

Given two sets of load resistances and output voltages: Rload = 108 ohms - Vout = 9.6V Rload = 10 Ohms - Vout = 2.3V Find the source voltage and the output voltage when R1 and R2 are equal. When the resistance is very large, the voltage seems to be around 9.6. My assumption was that then the...

Hey everyone, I'm hoping that you guys will be able to help me with some calculations. I was on YouTube and came across this: I then began to wonder if I could make a solenoid using bitter disk as in the video, granted no where near as powerful. I would say 1 tesla using an iron core. After...

Homework Statement [/B] It is required to find the current through the ammeter, marked A, in the above figure.Homework Equations ##V=iR##The Attempt at a Solution I've redrawn the circuit as follows - But don't know how to obtain the value ##i_3##

Not sure if this is more appropriate for physics or for differential equations, but this problem centers around an airplane traveling with air resistance. I am not looking to get the most realistic-possible model, as it is just for a video game I am making. Although this is technically a PDE...

Given the circuit, I am supposed to find the total resistance, but I am unsure of what to do without having a voltage or current source with an internal resistor.

Homework Statement [/B] I am working on a lab report regarding the creation of an electromagnet using an iron core solenoid (just a nail wrapped with copper insulated wire). Before continuing with the creation of the electromagnet, I had to answer some questions regarding my knowledge of...

Question Calculate resistance between terminals 1 and 2, 1 and 4, 1 and 3, 2 and 4, 3 and 4, and 2 and 3 My attempt of solution: For R between 1 and 2 i done: (R1 + R2) || (R1 +R2 + R3) The problem is: Im not sure how to find which is in series and what's in parallel so I'm confused and I...

Homework Statement 1. For the first measurement, a load resistance Rload = 119Ohms results in an output voltage V(OUT) = 11Volts. For the second measurement, Rload = 11Ohms results in an output voltage V(OUT) = 3.2Volts. From these two measurements, determine the output voltage V(OUT) when...

Homework Statement Homework Equations at point C: i2 - i3 - i4 i2 = i3 + i4[/B] The Attempt at a Solution I labeled all the currents going through each resistor in the picture[/B] for loop ABC: 2000i1 = 3000i2 + 4000i3 for loop BDC: 3000i5 = 2000i4 + 4000i3 at point C: i2 - i3 - i4 i2...

I've had a side project in mind for a while involving motorized Rollerblade wheels, however I need to figure out a motor size that would give me the needed torque to actually accelerate 250lbs up to 25mph. I realize even a 5hp electric motor is large but I was wondering if ohms have any affect...

Homework Statement 1. A sinusoidal source with RMS voltage V = 11Volts across a resistor R = 50Ohms, determine the dBm value. Hint: you will first have to determine the power delivered and then check the formula for dBm calculations. 2. A type of coaxial cable has a loss of 12dB/100m at some...

Homework Statement https://imgur.com/a/aVCeU Homework Equations (1/Req) = (1/Rv1) +(1/Rv2) Req = Rv1 + Rv2 The Attempt at a Solution I'm not sure which formula is the correct one to use.So.. I'm absolutely stuck. I tried downloading a bunch of circuit board simulators, but I couldn't find an...

Homework Statement The resistance of thermistor over a limit range of temperature is given by equation R=c/(T-203). Where c is constant ant T is absolute temperature. What would be temperature on centigrade scale of thermistor at absolute temperature T=300k? Homework Equations i)R=c/(T-203)...

Homework Statement [/B] Hi everyone! So I've got this similar problem as I posted yesterday, but this one is slightly different due to the presence of gravity: A particle in gravitational field ##~~g## starts traveling upward (positive direction) along the y-axis from ##~~y=0## with the...

1. 2D -problem A particle is moving on a frictionless, horizontal surface from ##O_{rigo}## with initial speed ## v_0 ##, as it faces the air resistance force ## F_R ##.2. ## F_R = -mαv ## (where v is a particle velocity) ## \frac {dv}{dt} + αv = 0 ##Show that: ## x(t) = \frac 1 α...

Homework Statement This is irodov's problem #310 in electrodynamics A long solenoid of cross-sectional radius a has a thin insulated wire ring tightly put on its winding; one half of the ring has the resistance ## \beta ## times that of the other half. The magnetic induction produced by the...

Greeting . It is clear to me that the resistor represents a physical obstruction to the passing current I do not know how exactly it works and I will try to show what I was really interested in the diagram.

Homework Statement 1) what is the total resistance of this circuit between points A and B? 2) if the horizontal resistor was replaced with an ammeter what would it read if a 6V battery was placed between points A and B? let R = 20 ohms Homework Equations The Attempt at a Solution had...

Hi friends, My question... At non resonance frequencies the resistance of primary is minimum or maximum? My analysis... There are two tuned circuit tuned to same frequency . In primary circuit at low frequency XL is low and large amount of current will flow at the inductor L1, now due to this...

Homework Statement "Find ##R_2## and ##R_3##, assuming negligible resistance ##r=0\frac{V}{A}##." ##R_1=6.1\frac{V}{A}## ##I_1=1.3A## ##I_3=4.8A## ##\epsilon = 24 V## Homework Equations Voltage in parallel circuits: ##V_1=V_2## or ##I_1R_1=I_2R_2## Total voltage: ##\epsilon =...

Homework Statement 2. Homework Equations [/B]The Attempt at a Solution so i was thinking i could take a look at small number of points and then generalize it but my method soon breaks down in the diagram i have denoted the resistance of the segment beside it if there is a bracket it means...

Homework Statement The output voltage, V_(out) (t) ‡ q(t) /C, effectively measures the charge on the capacitor as a function of time, where q(t) is an exponentially damped simple-harmonic oscillation: a) Given that L = 0.05 mH, the square-wave frequency is 25kHz, and the ringing decays to 40%...

1. The problem statement I did a laboratory work in which I had to find power and internal resistance. I used an ordinary battery so it's closed circuit. I did all tasks except writing a hypothesis and conclusion I can't really think of it. I don't know what to write since I just measure using...

Homework Statement Today I did a laboratory work in which I had to find power and internal resistance. I used an ordinary battery so it's closed circuit. I did all tasks except writing a hypothesis and conclusion I can't really think of it. I don't know what to write since I just measure using...

I know that electric conductivity of metallic conductors increases with decrease in its absolute temperature(kelvin) . But is it the same for electrolytes such as water. Is cold water a better or worse conductor of electricity than warm water at same pressure and concentration.

Recently I asked why with a multimeter you should not measure the resistance of a fuse in a car while there was still power reaching the fuse but why it was ok to measure the voltage. I was told the way resistance is measured is a small current is sent by the meter for the calculation to be...

Homework Statement Homework EquationsThe Attempt at a Solution Considering I- V characteristics graph, the slope for D.C. resistance is lower than that of the A.C. resistance. Now, the resistance is inverse of the corresponding slope. So, D.C. resistance should be more than A.C. resistance.

Homework Statement Homework EquationsThe Attempt at a Solution In the attached image the outer circular wire is represented as N . We have to find the equivalent resistance between O and N . Consider a battery of voltage V between O and N . From O there are six similar paths OA...

1. The Problem Statement Calculate the equivalent resistance between O and the circumference. Each wire has 24 ohm resistance and the circumference has zero resistance. 2. Homework Equations Not needed.3. Attempt at solution I tried to use symmetry to solve this problem. I understand that...

I don't understand how this is possible. This is a rather large transformer in a stereo system amplifier. The transformer is a simple step-down with 120V mains primary to a center-tapped secondary providing both 38V and 76V. According to ohm's law, at 120V this thing should draw about 85 amps...

I'm having a difficult time understanding why the internal resistance of the EMF source is disregarded in this problem. 1. Homework Statement You are asked to determine the resistance per meter of a long piece of wire. You have a battery, a voltmeter, and an ammeter. You put the leads from the...

Hello, I was giving a random thought to Ohm's Laws and thermal dilation. As a general rule we are told that ohmic resistors will increase their resistivity if their temperature increases. Does this take into account the fact that its dimensions will change due to thermal dilation? This would...

Homework Statement Homework Equations ## V=IR## The Attempt at a Solution This is an I-V graph so the slope must represent ##\frac{1}{R} ## Now, $$ R∝Temperature$$ {This is assuming that the wires are of metal} Now , since the graph is of ##\frac{1}{R} ## , the steeper the slope the higher...

Homework Statement I measured a battery rated at 1.5V(ε) and get 0.9V out and want to calculate the internal resistance (r). So, I model the battery as an ideal voltage source and a resistor in parallel. I know the voltmeter has a resistance of 1kΩ (R). How do I calculate the internal...

Homework Statement In Fig. 26-5, how large must R be if the potential drop from A to B is 12 V? (The figure has been pasted into the attached file). The answer to this problem is 3.0 ohms. I keep trying to solve this problem but I get a wrong answer. The answer I get from my calculations does...

Homework Statement A 60-cm long gold wire is soldered to a silver wire of the same length as shown in the diagram. If each wire is 2.00 mm in diameter, determine the equivalent resistance of the combination between A and B. Diagram is attached. Homework Equations R = ρL/A The Attempt at a...

Homework Statement 2. Homework Equations [/B] ## V = IR ## The Attempt at a Solution My solution: R1,R2,R3 are in parallel and so we can find their total R ## \frac {R1×R2×R3}{R1+R2+R3} = R'## ##R' = \frac {10}{3}## R' is in series with R4 ## ∴ R= R' + R4 = \frac{10}{3} +10 =...

Homework Statement H=I^2RT and H=(V^2)T/R. In one case H is directly proportional to R while in the other it is not where H is the energy consumed. Explain the apparent difference between the two cases Homework Equations None The Attempt at a Solution In the first case electricity is being...

Hi Guys I have metabolic syndrome, amongst other things. A friend has all the signs - sleep apnia, low testosterone, high AST, high ferritin, high blood pressure, horrid cholesterol, belly fat etc. Yet despite test after test he does not have insulin resistance. Me I am way insulin...

Homework Statement R1= 9 Ohms R2= 17 Ohms R3= 18 Ohms what is the total resistance of this arrangement? Express answer in ohms, correct to one decimal place. Homework Equations I used the Parallel circuit formula 1/r1 + r2 + r3 The Attempt at a Solution I got 4.0 Ohms, apparently, it is...

Homework Statement Homework EquationsThe Attempt at a Solution Can someone tell me what formula to use? Is it p=RA/L? but what about the mass? Thanks~

I wasn't exactly sure which forum I should post this question in but I felt this was the most appropriate one. So if there is a more appropriate one, feel free to relocate it (whoever is responsible for that). I wanted strictly a scientific answer to this question. How does weight affect a...

My hope is to explore [the existence of] dynamic correlation of plant tissue (leaves to start with) electrical resistance to stimuli. I've heretofore conducted experimentation reasonably sure enough of the techniques and materials I'll need that I've never posted for such advice in a public...

I wanted to ask. Since jets fly at great speed, often even supersonic, I'm curious about next things: 1) What is the relation between air resistance force and energy? 2) How does all that force resistance affect a pilot? 3) What protection do they have, if any? 4) And purely speculative...

Homework Statement Homework EquationsThe Attempt at a Solution [/B] I don't understand how can current in ammeter be zero .Why is 2V battery not sending current in the right loop ?

if a cell is running down, there would be a constant drop in p.d. across the cell, does the internal resistance of the cell increase or decrease?

Homework Statement A 4 pole lap wound armature has 16 coils, each with a resistance of 0.1 ohms. Calculate the resistance of the armature? Homework EquationsThe Attempt at a Solution Hi there fellow members, I'm currently doing a section of my course which deals with Electrical machines. The...