Resistance Definition and 1000 Threads

Disclaimer: Some of you might easily recognize that the components and circuit I am talking about are related to one of my projects, on which I had posted some months ago. Actually, the circuit is the same as the one in my project, but the one I am posting in this thread actually uses high...

I was following these [steps](https://www.allaboutcircuits.com/textbook/direct-current/chpt-10/delta-y-and-y-conversions/). I was calculating resistance for left side circuit. $$R_1=\frac{2 × 2}{2+2+4}=0.5\Omega$$ $$R_2=\frac{2 × 4}{2+2+4}=1\Omega$$ $$R_3=\frac{2 × 4}{2+2+4}=1\Omega$$ Then...

Am trying to find Effects of Feedback - Input resistance of this circuit. Is this the formula that in need to use to find the input resistance of this circuit ?

The question is to find the resistance between points A and F. I understand that the resistor between OC can be removed. From this point onwards, resistor OC has been removed. Let the far right point of the diagram, where i5 and i7 exit from, be B. Is it possible to detach the remaining...

I want to calculate the input resistance ,but i don't really know how to do it .am not sure is the formula R1(1+BA0)?

Summary:: Current through a certain resistor in a mixed dc circuit. Hi, Sorry if this is the wrong forum. I'm trying to work out the current through R1.The answer I need is 2 Amp, which I have confirmed with a simulation software. I have calculated the source current as 8A, the current past...

I'm trying to solve this problem using an rtz coordinate system, and Newtons second law. I know that mar = (m(v)2)/r. I'm failing to understand how mg and the drag force affects the solution and how I would set it up. I know if it was at the bottom of the circle that mg would be added to the...

Hello I,d like to find or to calculate Rolling resistance coefficient on sand tyre 37/12.5 R37. Thanks for your help

Should it be I3 = \frac{(R2+R4)}{(R2+R4) +R3} I or I3 = \frac{R2}{R2 +R3} I

Hi, I am trying to find the insulation resistance of a specific capacitor. I've posted on balancing resistors before and got some pretty helpful information. The previous datasheet gave the information in a different manner though. I'm hoping someone can help me decipher the insulation...

Homework Statement:: A K-type thermocouple is connected as shown to sense temperature. The temperature zone is at 25°C. The RTD has a resistance of 100 at 0°C and a TCR coefficient of 0.00385. A 5V power supply drives the circuit. Calculate R2 for proper compensation. What is the emf produced...

https://www.cnn.com/2021/02/16/health/neanderthal-gene-coronavirus-scn-wellness/

R1 = 2 ohms ; R2 = 2 ohms; R3 = 1ohm First figure: I need to calculate the resistance between: a) A and C and b) A and B a) R1 and R3 are in series => R13 = R1 + R3 = 3 ohms R13 and R2 are in parallel => 1/Rp = 1/R13 + 1/R2 => Rp = 1.2 ohms b) Here, between A and B there is only R1 so the...

Since both cylinders have the same material, this implies the density is the same. Length is also the same based on the question. We only need to compare the radii for resistance. R2 = pi ((2b)^2 - (2a)^2) R1 = pi (b^2 - a^2) R2/R1 = 4, so my answer is C. But, the given answer is A. Where did I...

I suppose the trick in this question is to realize that the drag acts in opposite directions when the ball ascends and descends and that the ball actually takes less time to rise and more time to fall than normally. I make a small sketch of the problem alongside. Attempt : The total time of...

The attached image (Horowitz & Hill Student Manual for 2nd ed) gives thevenin resistance and voltage for the network R_1+(R_2||R_L) as R_th=R_1||R_2 E_th=E_in(R1/(R_1+R_2)) E_th is self-evident (voltage divider) but how in the world they get R_th i beyond me. If there is no load, isn't R_1 in...

I was researching what the total electrical resistance of the human body was and got some quite far ranging values. It seems to range from 1, OOO to 1OO,OOO ohms. Some quite elaborate ways of testing it too. Then I thought I'd just get the old multimeter out. I have two and both measured about...

I have a burned stator for a PM generator mounted in the accessory case of an internal combustion engine. The stator has 2 sets of 5 coils creating 2 20 amp generators. I am using a lithium battery and the engine builder blames the battery for the burned stator. He says the lithium battery...

So I started doing this with formula: S is equal to π/2*(r2^2-r1^2) l is equal to h Is it correct ?

I am doing a physics lab where we are supposed to calculate air resistance and find the impacts of velocity and cross sectional area on air resistance. For the experiment, we rolled a cart down a ramp and measured data using Pasco Capstone software. When rolling the cart down the ramp, we...

A return path for the current was provided by the ocean itself. Given that the resistivity of seawater is about 0.25 ohm-meter, see if you can show that the resistance of the ocean return would have been much smaller than that of the cable. (Assume that the electrodes immersed in the water were...

I figured that when you close the switch the current from the upper cell will travel through the closed switch due to it being the path of least resistance, essentially the resistor between cells is unused (was my first thought). I'm not entirely sure how to progress with this question.

When we have electrical resistance it is based on dissipation of energy, when we have reactance it is a consequence of charge accumulation in capacitance. Together they form impedance. But let's consider what exactly is responsible for dissipation in case of resistance? Is not it because of...

Total acceleration equaled = -9.81

Hi all, I've been trying to follow a question I came across on a website. And I'm able to understand everything up until the separation of variables for solving the differential equation and coming to a solution with arctan. But there are a few things that aren't explained that I was hoping...

Why we say that the resistance of the series curcuit is equal to the sum of the resistances of the resistors?

So, I simply used the percentage increase formula for the resistance force, but what I come up with is a 9.5% increase, as opposed to the 44% it should be... Here's my procedure:

Hi, I'm trying to solve this integral and then isolate V, but I can't get the right answer. I don't know where is my errors. I probably muffed the integral. ##-bv -cv² = m\frac {dv}{dt}## ## \int_0^t dt = - m \int_{Vo}^v \frac {dv}{bv+cv^2} ## I get this after the integration ##t =...

I've tried doing it but i haven't been able to find the resistance of the diode.

I considered that the lengths of pi/4 and 3pi/4 would be in parallel: 1/R = 1/30 + 1/10 R = 7,5 ohm But the answer is 30 ohm. Where am I missing and how do I calculate the potential of the voltmeter.

Dear all, I have a very simple question. The rolling resistance (rr) of, say, a car, is defined as being proportional to the normal force/weight of an object. That seems reasonable: ##F_{rr} = C_{rr} \times F_N## The coefficient C_{rr} is a constant, depending on the materials. But now a...

Say that I have a round object on a table and it is still. If I apply a force and it doesn't move the resistive force is rolling resistance rather than a frictional force right? Now I must be able to apply forces in different amounts until it exceeds a boundary for the object to move similar to...

I'm a parent and have no idea, just looking for help please

How would we calculate the Thevenin's resistance for the above circuit? The right answer for this circuit is 1.5 kOhm. $$R_{567} = R_7 + (R_5 \parallel R_6) = .5 + .67 = 1.2 k\Omega$$ $$R_{34567} = R_3 + (R_4 \parallel R_{567}) = 1 + .75 = 1.75 k\Omega$$ $$R_{TH} = R_1 + (R_2 \parallel...

Not sure what I can do to proceed on here: Should I be using the Delta to Y transformation? Wouldn't be able to simplify using simple series and parallel circuits, and hence am looking for any clues I might need to solve this problem. PS: ForDelta to Y transformation, it seems that the 10 and 8...

I don't know about it. Please help. It wasn't letting me to post until I typed something here. So I am typing this.

Let us connect a battery of potential difference V to a wire. There is no resistance. Nothing! Now the battery creates some potential difference and the charges in the conducting wire move due to the Electric field created in the conductor by the battery. So, as the charge moves, its potential...

I have conducted an experiment which involves measurements of the velocities of a carriage moving in a straight line which has 4 polyurethane caster wheels attached to it. (The kind you can get a hardware store.) In one phase of the test the carriage is pushed at about .1 meters per second. In...

I don't know if this is a dumb question, but I just can't seem to wrap my head around it. I can imagine and feel when I'm pressing against a wall, that there's a force. Especially when the wall is not moving, I can continually increase the strength of my push and feel a greater resistance from...

Hello, i am currently working on a project where i have to calculate the internal resistance of a battery based on the voltage drop caused by placing a resistor over the battery. I am an EE, and i understand how i can calculate the IR by schematic, but i found this equation: ((Open circuit...

2500 N [south] + 3200 N [south] = 5700 N [south] 5700 N [south] - 6000 N [north] = 300[north]

To find total resistance between 22 Ω, 14 Ω and 4.5 Ω should I use delta - Y formula? Or there is other simpler way? Thanks

Summary:: I have a question that I don't understand but you may know where r was come from. I mentioned about my question on the addition.

I have attached my solution to this problem but I think I got the wrong answer.

By the use of symmetry, I have found that equal currents will flow through opposite edges like A-C and C'A', but still, the use of kirchhoffs current and voltage laws lead to four equations in four variables which I am not able to solve, neither I am sure that the four equations which I have...

This was an exercise from the 2011 admission test of an university from Brazil: 40 identical generators with electromotive force 1,5V and resistance 0,25 Ohms and one resistor with resistance 2,5 Ohm are associated in such a way that the 2.5- resistor dissipates the greatest energy per second...

I explained what I want to tell you in the picture I add. Thanks in advance.

Hello Guys, I really need help, I am trying to simplify this circuit to calculate Rth and I got stuck.