Voltmeter Definition and 152 Threads

http://img295.imageshack.us/img295/6016/55877904.th.jpg I tried everything to solve this. XL and XC are an inductor and a capacitor (respectively). I start with the idea that there are 50 V on each of them, and that a current of 5 A flows between, and that the generator has no effect, because...

Homework Statement a resistor of 600 Ω and one of 400 Ω are connected in series and their combination is being supplied by 90 V. A voltmeter that is connected on edge of the resistor of 600 Ω shows 60 V. a) what's the internal resistance of the voltmeter. The Attempt at a Solution i...

how to design a series multi-range voltmeter with its voltage range is given but its value of full scale deflection current (I fsd) and internal resistance (R m) is not given? the voltage range given is 0-3V, 0-9V and 0-30V. since to find the value of every single multiplier resistor is: R...

The question asks to derive the equation you need to find the resistance of a voltmeter in a simple RC circuit like the one shown here: http://people.ee.duke.edu/~cec/final/node32.html But R2 in the link is actually a capacitor in my circuit. The equations in the lab journal are Vc=q/C...

Homework Statement I'm writing my sources of error for my lab report and I'm just wondering if its true that the ammeter has internal resistance in it, and that this will increase the resistance in the circuit, which will ultimately decrease the current in the circuit?? Does this sound right...

Homework Statement A voltmeter reads 8V at full scale deflection, and is graded according to its resistance per volt at full scale deflection as 5000 ohms / volt. How will you convert it into a voltmeter that reads 20V at full scale deflection? Will it still be graded as 5000 ohms / volt...

Homework Statement A voltmeter will be used to measure the voltage vA in the circuit below. Assume that the voltmeter has a resistance of 100[ohms] and a full-scale voltage of 20[V]. a) What will the voltmeter read? b) What is the percentage error in making this reading?Homework Equations...

Homework Statement A very long insulating cylindrical shell of radius 6.00 cm carries charge of linear density 8.90*10^-6 C/m spread uniformly over its outer surface. *What would a voltmeter read if it were connected between the surface of the cylinder and a point 4.70 above the surface...

Homework Statement You have a power supply of 10 V. It is connected in series to a 2 ohm resistor and a 5 ohm resistor. You take the voltage across the 5 ohm resistor with a voltmeter that has an internal resistance of 3 ohms. What is the current through the voltmeter?Homework Equations The...

so here are my questions: Does a single capacitor take longer to discharge than two capacitor is series? Why? Would the voltage also be lower when discharging in series? In discharging a capacitor, if a resistor is not a part of the circuit, does it discharge through the voltmeter's...

When working out circuits problems, can we consider a voltmeter to read the difference in the scalar potential between two points Voltmeter = V(b) - V(a), or does it tell us a "path potential" / work to move a test charge along a path Voltmeter = -\int_a^b \mathbf{E} \cdot d\mathbf{l} ?

Can someone please help me out with this problem? I am not sure if what I am doing question: The figure below shows the internal wiring of a "three-scale" voltmeter whose binding posts are marked , 3.00 V, 15.0 V, and 150 V. When the meter is connected to the circuit being measured, one...

Homework Statement Given the following: • a battery, • a digital voltmeter (which records voltage as a function of time), • a digital ammeter (which records current as a function of time), • a battered industrial capacitor, • two copper plates, • and several bits of copper wire...

The setup shows a Galvanic cell connected to a voltmeter. The question asks how the reading of the voltmeter would change if the voltmeter's resistance became finite (instead of infinite) and current started to pass through the voltmeter. The answer given is "The reading will decrease because...

Can someone explain how I can find the resistance of an ohmic resistor of unknown resistance by setting up a simple circuit using a voltmeter and household appliances? Thanks

Homework Statement A little help with this one please The power in a 10ohm resister when connected to a 100v supply is measured by an ammeter and voltmeter. There are two possible ways of connecting the instruments (as seen in the attachment) The values of Ra and Rv represent the...

Homework Statement When you hook up a voltmeter to a circuit, you are providing another possible pathway for current—that is, through the voltmeter. Usually this is not a problem, provided that the resistance of the voltmeter is much larger than the resistance of the circuit. Suppose you have...

Homework Statement A circuit you're building needs a voltmeter that goes from 0 to a full-scale reading of 5.0 V. Unfortunately, the only meter in the storeroom is an ammeter that goes from 0 to a full-scale reading of 500 microA. It is possible to use this meter to measure voltages by...

A voltmeter with internal resistance of 100k ohm reads 40V across the 200k ohm resistor of the circuit. Determine the actual voltage across the resistor( without the voltmeter) my anawer: across 100k ohm = 13V across 200k ohm = 26.7 V is it correct ? but it seems to be wrong.. so...

Homework Statement How must a voltmeter be connected in a circuit to measure voltage across a resistor and why? Homework Equations Vv=Ifs(Rc+Rs) The Attempt at a Solution I think the voltmeter must be connected parallel to the series with its terminals on either side of the resistor.

Homework Statement "Design a multirange voltmeter capable of full-scale deflection for 20.0V, 50.0V, and 100 V. Assume that the meter movement is a galvanometer that has a resistance of 60.0 ohms and gives a full-scale deflection for a current of 1.00 mA"Homework Equations V = IR Kirchoff's...

the moving iron voltmeter has resistance of 5k ohm at 15c when it reads correcectly when connected to a supply of 200V. and the copper coil's temperature coefficient at 15c is 0.004ohm/c. so what's the percentage error in the reading when it's 50c?

Homework Statement Hi all. Lets say a voltmeter registers (measures) the following quantity: V = \int_a^b{\textbf E\cdot d\textbf l} Does this mean that it measures V = V(b)-V(a), i.e. the potential at b subtracted by the potential at a? Thanks in advance.Niles.

Homework Statement A circuit consists of a series combination of 6.00 -kOhm and 4.50 kOhm resistors connected across a 50.0-V battery having negligible internal resistance. You want to measure the true potential difference (that is, the potential difference without the meter present) across...

Homework Statement A 85 V battery has an internal resistance of r = 5.73 ohms . (a) What is the reading of a voltmeter having a resistance of R_v = 482 ohms when placed across the terminals of the battery? ___________ V (b) What maximum value may the ratio r/R_v have if the...

Homework Statement A very long insulating cylinder of charge of radius 2.70cm carries a uniform linear density of 16.0 nC/m Question: If you put one probe of a voltmeter at the surface, how far from the surface must the other probe be placed so that the voltmeter reads 195 ? Relevant...

This circuit was used to make a digital volt meter. What I'm confused about is the exact use of the potentiometer on the RHS of the diagram. I know is was used to set the "reference voltage" to 4V and all all output voltages from the meter would be from 0-3.999 volts when displayed. The...

Homework Statement The circuit in the attached figure (excuse the terrible drawing, I suck at using the paint feature) all meters are idealized and the batteries have no appreciable internal resistance a) Find the reading of the voltmeter with the switch S open b) With the switch...

Hi, I did a practical today in class, and I got curious and did another setup of my own [Setup 2 in the attached diagram], and I have a question about the voltmeter. As attached, when I did Setup 1 and Setup 2, the reading on the voltmeter for Setup 2 was quite higher. Why would this be? I...

[SOLVED] Voltage Query Homework Statement An insulating spherical shell with inner radius 25.0 cm and outer radius 60.0 cm carries a charge of + 150.0 \mu C uniformly distributed over its outer surface. Point a is at the center of the shell, point b is on the inner surface and point c is on...

For the circuit both meters are idealized, the battery has no appreciable internal resistance, and the ammeter reads 1.25 . What does the voltmeter read? What is the emf of the battery? I tried this: 15 ohm and 10 ohm resistors are in series, hence equivalent to 25 ohm. Three...

Homework Statement A voltmeter with resistance R_V is connected across the terminals of a battery of emf EMF and internal resistance r. Find the potential difference V_meter measured by the voltmeter. Homework Equations v=IR Vab= Va -Vb The Attempt at a Solution tried using...

why we convert a galvanometer into voltmeter and ammeter?

Hello all, I made a custom power supply using a standard ATX computer PSU. I took the -12V and +12V leads to get 24V then put a LM338 on the positive side for a 1.25V to 22V adjustable ouput. Works great. I wanted to put a digital voltmeter on the adjustable output so I would know what...

Hi, my lab is using these: http://www.elexp.com/tst_7050.htm we weren't given any intro on interpreting the results. we're measuring dc volts... its the black numbers below the shiny metal in the picture. anyway, theirs two sets of numbers for dc volts, so we don't know which to use...

Assuming a simple circuit with a couple of resistors Would it just read 0 around 2 points uninterrupted by a resistor?

Homework Statement The problem is actually longer, but I will make it shorter, just to ask my question. A flashlight battery has a voltmeter connected across its terminals. The voltmeter reads 1.50 V. (Assume the voltmeter is perfect, with an infinite resistance, drawing no current.) The...

While studying about 'Potentiometer' it's said : "The resistance of the voltmeter be large compared to the circuit resistance across which the voltmeter is connected.Otherwise an appreciable current will flow through voltmeter which will alter the circuit current & the P.D to be measured". Can...

hello i know why an ammeter is always in series with the resistor(s) but i don't know why a voltmeter is in parallel with the resistor(s) can somebody explain this? thank you:D

Do voltmeters work by sampling current from two points in a circuit and output the voltage or potential difference between the two points? Must there be resistor in the middle of the two points? Since V=Ed. there dosen't have to be does there? Sometimes the voltmeter gives a negative reading...

A galvanometer of coil resistance 50 ohms deflects full scale for a current of 3.5 mA. What series resistance should be used with this galvanometer to construct a voltmeter which deflects full scale for 35 Volts?

Please excuse my ignorance, but I could use some assistance. I need to get a device that will test if current can pass from an electrode through a connected wire on down to a pin that connects to a computer port. (Sometimes the electrical connection fails because of a poor connection between the...

I am trying to design a 3 1/2 digit 20V voltmeter using the ICL7106 and I was wondering if anybody could help me with a few things: 1. How could I get it callibrated to a max 20V reading? 2. I will be using it as an onboard voltmeter for a variable DC power supply. If I tap the source 18V...

I am building an autoranging digital voltmeter as the subject line suggests and am having a problem with the ICL7107 chip that I am using. Looking at figure 15 on: http://www.intersil.com/data/fn/fn3082.pdf specifically RefHI and RefLO, with a 2V max input difference between the pos and neg...

I am building an autoranging digital voltmeter as the subject line suggests and am having a problem with the ICL7107 chip that I am using. Looking at figure 15 on: http://www.intersil.com/data/fn/fn3082.pdf specifically RefHI and RefLO, with a 2V max input difference between the pos and neg...

We were asked to design digital voltage and current meter with 3 ranges (20 100 200) v for voltages and two ranges (2, 20)A for amperes Note: supply voltage is 5V maximum value for resistors of ampere meter must not exceeded 0.5 ohm V1=Vin. (R2+R3+R4)/(R1+R2+R3+R4)...

Why is that when I introduce an ammeter or a voltmeter into a circuit, it alters it. In other words how does a *meter affect the circuit? I read somewhere that when you measure the resistance [using an ammeter], it is slightly different from the actual value. Why does this happen? And one more...

Why can a voltmeter potentially load a circuit?

1. 　－－－－┤├－－－－（ammeter）－－－－－－－ 　　　　｜　 cap 　　　　　　　　　　　　　　 ｜ 　　　　｜　　　　　　　　　　　　　　　　　　｜ 　　　　└－－－－－－（voltmeter）－－－－－┘ 　　　　　 2. 　－－－－┤├－－－－（ammeter）－－－－－－－ 　　　　｜ cap　 　　　｜ 　　　　｜　　　　　　 ｜ 　　　　└ (voltmeter)┘ Two different arrangement of voltmeter are used to measure the...

This is another problem I am having troubles with. Here's the prompt: What is the reading of a voltmeter with the proper range and with resistance 5*10^4 Ohms when connected between point b and ground? I know that for voltmeters, V = I_fs (R_c + R_s), and I tried solving for V using the...