# Ppt on galvanometer to ammeter

##### Potential Dividers You will be familiar with the use of a variable resistor to vary current.

along its length and we assume none flows through the voltmeter. S AB 2 volt Centre Zero galvanometer - a very sensitive ammeter. V For practical purposes a resistor is frequently placed in series with the galvo to protect it from high currents.  Suppose the voltage from A to S is the same as the emf of the second cell. S AB 2 volt Centre/

##### MAGNETISM AND ELECTRICITY

Science 1, Class IX Objectives Magnetism Magnetic effect of electricity Oersted’s experiment Right hand rule Tangent Galvanometer RECAP Magnet - material that produces a magnetic field Magnetic field: invisible a force that pulls /that have a high melting point are used. e.g. tungsten, sodium, mercury Ohm’s law Observations Experiment to find out the ratio between potential difference and electric current A – ammeter, V – voltmeter B – electrical cell X – resistance S – plug key Rh – rheostat (electrical /

##### From Electric to Electronic From the JUs to the Vacuum Tube.

meters such as voltmeters and ammeters until they were largely replaced with solid state meters. Back to Business Mrs. Houston! So what about this Galvano-froggy-thingy? Aha! The Fleming Valve Sir John Ambrose Fleming -1904 Worked to develop the first rectifier while / strength of the current. At the receiving end the radio waves were difficult to detect with a galvanometer, but Fleming realized that if he could get the current to flow in only one direction, the oscillations of the wireless signal could be /

##### To return to the chapter summary click Escape or close this document. glencoe.com Image Bank Foldables Video Clips and Animations Standardized Test Practice.

an electromagnet. Each time the electromagnet is turned on, the doorbell rings. To return to the chapter summary click Escape or close this document. Question 4 Chapter Review What device would you use to measure the current in a circuit? A. motor B. ammeter C. galvanometer D. generator PS 4.4 To return to the chapter summary click Escape or close this document. Answer Chapter Review The/

##### What is magnetism ? The force of attraction or repulsion of a magnetic material due to the arrangement of its atoms, particularly its electrons. The earliest.

more coils wrapped around the core, the stronger the magnetic field that is produced. This stronger magnetic field leads to a stronger current What is a galvanometer ? A galvanometer is an electromagnet that interacts with a permanent magnet and acts as an ammeter to measure current. Galvanometers are used as gauges in cars (part of the speedometer and odometer) What are electric motors? An electric motor/

##### Current Electricity. The movement of electric charge from one place to another. The movement of electric charge from one place to another.

amount of electricity passing a point. Measured in amperes (A) Measured using an: Ammeter- larger currents Galvanometer- smaller currents High Current Low Current High Current Low Current Resistance Resistance Resistance The measure of an objects opposition to the passage of a steady electrical current The measure of an objects opposition to the passage of a steady electrical current Measured in ohm’s (Ω) Measured in/

##### Electricity Basic ideas… Electric current is when electrons start to flow around a circuit. We use an _________ to measure it and it is measured in ____.

all the bulbs are the same what is the total resistance in this circuit? Total R = 5 + 5 + 5 = 15  Voltmeter reads 10V Ammeter reads 2A More examples… 12V 3A 6V 4V 2A 1A 2V What is the resistance of these bulbs? Practice with Ohm’s Law OhmsVoltsAmps 410025 1515010 23015 9455/When it’s balanced) R 2 R 4 if the temperature of one of resistors is changed, current will flow through the galvanometer. This current can be used to activate a second circuit such as a heater or an alarm. I r 1 r 2 r 4 r 3 AC B/

##### Journal #15 2/22/12 Use what you learned in yesterday’s lab to predict which picture shows magnetized atoms and which shows non-magnetized atoms.

the permanent magnetic field causes the loop to rotate. Galvanometer Galvanometer                                                                                                                                                            Galvanometer Galvanometer - the historical name given to a moving coil electric current detector./ to the coil may be proportional to the current passing through the coil. Such "meter movements" were at the heart of the moving coil meters such as voltmeters and ammeters /

##### Average: 71 % Top grade: 100 % ☺ Make sure you go through your test and the solutions carefully to understand where you went wrong. Ask me at office hours.

that magnetic field sensed by compass is increased: So can detect very small currents – called a galvanometer More common design for galvanometer - Magnet held stationary. Many loops of wire, so more sensitive; rotates when current is flowing, and deflects a spring. Can be calibrated to measure current (ammeter), or voltage (voltmeter). Electric motors Designed so that deflection makes a complete rotation (instead of partial/

##### Average: 71 % Top grade: 100 % ☺ Make sure you go through your test and the solutions carefully to understand where you went wrong. Ask me at office hours.

that magnetic field sensed by compass is increased: So can detect very small currents – called a galvanometer More common design for galvanometer - Magnet held stationary. Many loops of wire, so more sensitive; rotates when current is flowing, and deflects a spring. Can be calibrated to measure current (ammeter), or voltage (voltmeter). Electric motors Designed so that deflection makes a complete rotation (instead of partial/

##### Chapter 12. What is Magnetism? Magnetism is the force of attraction or repulsion of a magnetic material due to the arrangement of its atoms, particularly.

, the more it interacts with the permanent magnet. Galvanometers are used as gauges in cars and many other applications such as electric meters (ammeter, voltmeter) What are electric motors? electrical energymechanical energy  * An electric motor is a device which changes electrical energy into mechanical energy.  In an electric motor the current is made to change direction each time the coil makes a half/

##### LOCATION OF CABLE FAULTS INTRODUCTION: Cable fault is referring to something that occurs current can’t flow smoothly. It is because open circuit or short.

and Q are two ratio arms consisting of st6ep resistors or slide wire, G is galvanometer, E is a battery and S1 is a battery key. In this method, sound cable is connected to faulty cable for find actual happen fault. Fig.6 is connection method of Murray Loop /together at the distance and as shown by a lo0w resistance connection. The current is measured by using a resistor R and an ammeter A. By using throw over switch S, the voltmeter V whose one terminal is earthed is connected first across the section cd of/

##### Intermediate elements

= Fixed resistor SNGCE Wheaston’s DC bridges R2 = unknown value of R1 , R3 = Fixed resistor R4 = Variable resistor e= Galvanometer with high sensitivity V = Source 16 April 2017 DEEPAK P SNGCE Wheaston’s bridges 16 April 2017 DEEPAK P SNGCE Wheaston’s bridges 16/ is that the direct current system employs a voltage to current converter while the direct voltage system uses a voltage amplifier Receiving-End Scheme: The end device is a PMMC milli-ammeter as it has to read the value of the line current at the /

##### Basic Instruments and Measurements Chapter 2. Basic Analog Meter D’Arsonval movement – stationary magnet, moving coil galvanometer. Iron Vane Meter –

Basic Analog Meter D’Arsonval movement – stationary magnet, moving coil galvanometer. Iron Vane Meter – two pieces of iron are placed inside a hollow core solenoid. Current causes magnetic field to move a needle. Extreme caution and care when handling an analog/. Note what range the dial of meter is set to when reading the value of the scale. Ammeter Measures electrical current in a circuit. –Amperes –Milliamperes –Microamperes Shunt is used to direct excess current away from meter. Always connected in /

##### Welcome! The Topic For Today Is…. Your Topic Tools we use to measure Resistance and Resistivity Current Electricity Series and Parallel Circuits Cut out.

1: 400 Question: Voltmeters measure… Answer Potential Difference Topic 1: 600 Question: Ammeters are connected in while voltmeters are connected in. Answer Series; Parallel Topic 1: 800 Question: Ammeters have resistance while voltmeters have resistance. Answer Very little; Very much Topic 1: 1000 Question: A galvanometer is… Answer A device to measure extremely small currents. Topic 2: 200 Question: What is resistivity? Answer Resistivity/

##### MODELLING & MEASURING ELECTRICITY. TERMS TO DESCRIBE ELECTRICAL CURRENT  Voltage  Current  Resistance  Conductors  Cells  Electrons “flow” through.

VOLTAGE DROP  The potential difference across a resistor or device.  Millivoltmeters: are meters used to measure small voltages. AMMETERS  Are used to measure electrical current in amperes.  Remember that current is the rate of flow of electricity / You can insert the ammeter between any two circuit components and still show the same reading.  The current is the same at every point in the loop.  Meters used to measure small currents are sometimes called galvanometers. MULTIMETERS  Meters with several/

##### And Electricity! Chapter 8 Section 2.  1820: Hans Ørsted happened to have compass close to a wire with current flowing  The compass needle deflected.

▪ Movement of the cone makes sound ▪ HowStuffWorks "How Speakers Work" HowStuffWorks "How Speakers Work"  GalvanometerGalvanometer has a fixed magnet and a coil of wire making an electromagnet  When current goes through electromagnet it is/moves  Needle attached to moving coil measures amount of current ▪ Voltmeter ▪ Ammeter  Electric motor  Electromagnet that can rotate between poles of permanent magnet  Current through electromagnet makes it attracted and repelled to poles of permanent magnet/

##### INTRODUCTION TO SENSORS Introduction to Sensors Learning Module Micro-Pressure Sensor.

of energy  Detect changes in or the transfer of energy  Detect by receiving a signal then responding to that signal  Convert a signal into a readable output 350° F 278° F Setpoint Thermocouple Sensor electronics /Barometer Diagram of Aneroid Barometer 8 Revised 04/02/2012 Electrical Sensors  Ohmmeter  Voltmeter  Galvanometer and ammeter  Watt-hour meter Schematic and photograph of a Galvanometer used for sensing electrical currents 9 Revised 04/02/2012 Chemical Sensors  Carbon dioxide detector /

##### MagnetismSection 2 Electromagnetism 〉 What happens to a compass near a wire that is carrying a current? 〉 When the wire carries a strong, steady current,

. electric motor: a device that converts electrical energy to mechanical energy Galvanometers detect current. –galvanometer: an instrument that detects, measures, and determines the direction of a small electric current MagnetismSection 2 Electric Motor MagnetismSection 2 Electromagnetic Devices, continued ammeter: measures current voltmeter: measures voltage. Motors use a commutator to spin in one direction. –commutator: a device used to make the current change direction every time the/

##### THE PROPERTY OF A MATERIAL/OBJECT TO ATTRACT OTHER OBJECTS MADE OUT OF IRON, MAGNETITE, OR STEEL Magnetism.

completely reverses itself every million years or so! Diamagnetism, Paramagnetism and Ferromagnetism: Diamagnetism:  The effect of materials to slightly repel magnets of either polarity.  Silver, lead, and copper Paramagnetism:  Slightly attract magnets of either/ when using a compass under a wire. Meters Galvanometer-detects current When calibrated it can measure current (ammeter) or voltage (voltmeter) Motors By modifying a galvanometer you can make an electric motor http://electronics.howstuffworks/

##### Copyright © 2009 Pearson Education, Inc. Admin: Discussion sections start tommorrow. Very useful prep for tests. You are expected to attend. From the lab.

Education, Inc. Question on next week’s assignment!! Copyright © 2009 Pearson Education, Inc. An ammeter measures current; a voltmeter measures voltage. Both are based on galvanometers, unless they are digital. Ammeters and Voltmeters current is passed through a coil in a magnetic field coil experiences a torque proportional to the current. If the coils movement is opposed by a spring, then the amount of/

##### What you will learn: You will relate magnetism to electric charge and electricity You will describe how electromagnetism is harnessed to produce mechanical.

out of the field, depending on the direction of the current 6. The motion of the coil causes the cone to vibrate, creating sound waves in the air B. Galvanometer 1. Device used to measure very small currents 2. Used in voltmeters and ammeters. 3. A small loop of current carrying wire is placed in a strong magnetic field 4. One side of loop/

##### AN INTRODUCTION TO… MODERN PHYSICS Maxwell’s – Good to the last…. In 1873, James Clerk Maxwell summarized in 4 equations everything that was known.

. Shedding light on Problem #2 Physicists’ understanding of EM was challenged with another experiment: The Photoelectric Effect In the experiment, light was incident on a metal plate which was attached to a wire. The wire was connected to a galvanometer (a sensitive ammeter). The Photoelectric Effect A simulation of the Photoelectric effect When certain light shines on the metal, current passes through the/

##### AN INTRODUCTION TO… MODERN PHYSICS. Let There be Light… In 1873, James Clerk Maxwell summarized in 4 equations everything that was known about EM and.

. Shedding light on Problem #2 Physicists’ understanding of EM was challenged with another experiment: The Photoelectric Effect In the experiment, light was incident on a metal plate which was attached to a wire. The wire was connected to a galvanometer (a sensitive ammeter). The Photoelectric Effect A simulation of the Photoelectric effect When certain light shines on the metal, current passes through the/

##### A Unit 4 Review. When an object is charged, it has an imbalance of electrons. Static electricity is another term used to describe this. You can charge.

like a switch  Current is the flow of electrons.  It is measured in amperes (A) using a galvanometer (weak current) or an ammeter (larger current).  Voltage is the potential difference in energy between two points in a circuit.  It / energy.  An electromagnet rotates within a field magnet. When magnets repel & attract, this created a rotating motion. This motion allows for work to be done!  Please see diagrams in Topic 6.  Power Generating Station   Step up transformer   High Voltage Power lines /

##### Introduction to Current In AP C Current I = dq/dt I: current in Amperes (A) q: charge in Coulombs (C) t: time in seconds (s)

nd Rule Loop rule. The net change in electrical potential in going around one complete loop in a circuit is equal to zero. Conservation of energy. Using Conventional Current & the Loop Rule Internal resistance of real batteries Through resistors: Going with the/- I 1 5Ω +8V= 0 So I 1 = +1.38 Amps and I 3 = 1.02 Amps Terminology: galvanometers measure small currents (mA), while ammeters measure large currents (whole Amps) Variable Resistors BQ V 12 Volts 330  For the drawing shown, calculate a) the current /

##### Introduction to Current In AP C Current I = dq/dt I: current in Amperes (A) q: charge in Coulombs (C) t: time in seconds (s)

batteries aren’t necessarily ideal; they can have internal resistance that reduces voltage output 6) you may need to use a loop rule to figure out voltage drops Using Conventional Current & the Loop Rule Internal resistance of real batteries Through resistors: Going/wrong. It means you chose your current to be in the wrong direction initially. -0.545 A Applying Kirchhoff’s Laws 2.18 A 2.73 A Terminology: galvanometers measure small currents (mA), while ammeters measure large currents (whole Amps) Variable /

##### Introduction to Current In AP C Current I = dq/dt I: current in Amperes (A) q: charge in Coulombs (C) t: time in seconds (s)

batteries aren’t necessarily ideal; they can have internal resistance that reduces voltage output 6) you may need to use a loop rule to figure out voltage drops Using Conventional Current & the Loop Rule Internal resistance of real batteries Through resistors: Going/wrong. It means you chose your current to be in the wrong direction initially. -0.545 A Applying Kirchhoff’s Laws 2.18 A 2.73 A Terminology: galvanometers measure small currents (mA), while ammeters measure large currents (whole Amps) Variable /

##### 1 N S Magnetic field lines ALWAYS run north to south. The number of magnetic field lines denotes the strength of the magnetic field (B). The more lines.

was demonstrating an experiment for students when he accidentally discovered that a compass needle moved when it was close to a wire connected to a battery. Professor Hans Christian Oersted 4 B I Oersted noticed that if the current was running in /14 SN HAIR SPRINGS CONTROL MOVEMENT AND ALLOW CURRENT TO ENTER AND LEAVE THE COIL RADIAL SOFT IRON POLE PIECES COIL PERMANENT MAGNET MOVING COIL METER SOFT IRON CYLINDER This is seen in any analogue meter: Galvanometer Ammeter Voltmeter 15 SN + + This shows the /

##### Tennessee SPI Objective: Select tools and procedures needed to conduct a moderately complex experiment. Notes Science Essential Questions 1 ) Which tools.

and Procedures Take Notes: just copy down the green text Ex: Medical researchers might test a new flu virus vaccine to learn how many people it protects from the flu. (quantity). Ex: Software designers might measure the “playability” of /measure: pH scale from 0 to 14 Scientific Tools …you might use a galvanometer to measure electrical current -measures both the strength and direction of electrical current In an experiment… …to just measure the current you could use an ammeter Scientific Tools …you also /

##### Bell Ringer Give an example of something that you observed over break which involved physics. Be sure to thoroughly explain your answer.

to/themselves to the poles of / behave similarly to electric charges/ It is possible to weaken a magnet /field to move a plunger /to the magnetic field, no deflection occurs For particles moving perpendicular to/to establish a field where an electromagnet is made to rotate –When connected to/to keep spinning Motors As the armature passes through the horizontal position, the poles of the electromagnet reverse due to/Galvanometer: A sensitive instrument used to detect electric current –Consists of /

##### Sensors. What Are Sensors? Devices that change resistance due to – Light – Pressure – Position (angle) –etc… Haptic Perception - involves sensors in the.

arm. These different receptors contribute to a neural synthesis that interprets position, movement, and mechanical skin inputs. Thermal temperature sensors: thermometers, thermocouples, temperature sensitive resistors (thermistors and resistance temperature detectors), bi- metal thermometers and thermostats heat sensors: bolometer, calorimeter Electromagnetic electrical resistance sensors: ohmmeter, multimeter electrical current sensors: galvanometer, ammeter electrical voltage sensors: leaf electroscope/

##### Mr. Gillis’ Science Class. What needs to happen to get the bulb to light?

has been done in B, therefore it has a greater Potential Energy! Electric Circuit  A complete pathway that allows electrons to flow  Transforms electrical energy into other forms of Energy  Interactive website Interactive website Conductor – wire through which current flows/ of charge passing a given point in a conductor per second measured in amperes (A) by an ammeter or (mA) by a galvanometer Electrical Resistance:  Slows down the flow of electrons and transforms electrical E into other forms of E/

##### Electricity Principles and Technology. Have you ever wondered??? How does electricity get to our wall sockets How does it know exactly how much we need?

(A) 1 A = 1 coulomb = energy in 6.25 x 10 18 Measuring Electric Current Galvanometer – measure small or weak electric current Ammeter – measure larger or strong currents Voltage Potential difference is the same as Voltage The difference in electric /gases. Pollutants react With the chemicals In the water and Are removed Generating Electricity 2. Hydro-electric plants (kinetic to electric) http://ga.water.usgs.gov/edu/hyhowworks.html Generating Electricity 3. Thermonuclear plants http://www.msnbc.msn.com/id/

##### SPI 0807.5.4 (Biodiversity) Identify several reasons for the importance of maintaining the earth’s biodiversity. 8 Reasons to Maintain Biodiversity 1)

acidity and basicity -unit of measure: pH scale reading from 0 to 14 Notes Science SPI 0807.Inq.2 (Tools and Procedures) Scientific Tools In an experiment… …you might use a galvanometer to measure electrical current …measures both the strength & direction of electrical current …to just measure the current you could use an ammeter Notes Science SPI 0807.Inq.2 (Tools and Procedures) Scientific Tools

##### Welcome to Physics Course Welcome to Physics Course Electromagnetic (1) Course Code: 2210 Phy Lecturer Dr: Asma M.Elbashir e.mail

Course Report Electrical Meters 1.The Galvanometer 2. The Ammeter 3. The Voltmeter The electric field and potential difference: 1.Electric charge, electric force. 2.Coulomb’s law. 3.Electric field. 4.Analysis of electric force. 5.Gauss’s law and its applications. 6.The Potential Energy and Potential Difference. 7.Electric Potential and Potential Energy due to Point Charge. 8.Motion of/

##### (nz345.jpg)my office!

means a current of I G =1A produces a full-scale deflection of the galvanometer needle. The needle deflection is proportional to the current I G. If you want the ammeter shown to read 5A full scale, then the selected R SHUNT must result in I / V AB (=V SHUNT )? A galvanometer-based ammeter uses a galvanometer and a shunt, connected in parallel: G RGRG RSRS IGIG ISIS I Example: what shunt resistance is required for an ammeter to have a resistance of 10 m , if the galvanometer resistance is 60  ? The shunt/

##### PHYSICS – Electric circuits. LEARNING OBJECTIVES Core Draw and interpret circuit diagrams containing sources, switches, resistors (fixed and variable),

as a rectifier Recognise and show understanding of circuits operating as light-sensitive switches and temperature-operated alarms (to include the use of a relay) Draw and interpret circuit diagrams containing sources, switches, resistors (fixed and variable), heaters, thermistors, light-dependent resistors, lamps, ammeters, voltmeters, galvanometers, magnetising coils, transformers, bells, fuses and relays Draw and interpret circuit diagrams containing diodes Draw and interpret/

##### Chapter 15 Electric Circuits

of the circuit is R + r where r is the resistance of the ammeter. Adapt a galvanometer to measure a large current (an ammeter) Shunt: add a resistor in parallel with the galvanometer. The adapted galvanometer has a smaller resistance. moving-coil galvanometer the ammeter + - shunt R Adapt a galvanometer to measure a large current (an ammeter) Example: A moving-coil galvanometer with f.s.d. current 1.0 mA is adapted/

##### Quote of the day. Week 2: Voltage & Current Measurement.

(which respond to both dc & ac)irongauge Ammeter Design  An ammeter is placed in series with a circuit element to measure the electric current flow through it.  The meter must be designed offer very little resistance to the current so that it does not appreciably change the circuit it is measuring.  To accomplish this, a small resistor is placed in parallel with the galvanometer to shunt most of/

##### Mutual Inductance As in a transformer, changing the current in the primary coil causes an induced voltage in the secondary coil i.e. mutual induction.

; and 3.explain the reading of each meter when the switch is opened again. Mutual Inductance: Ammeter swings to 5 A Simultaneously the Galvanometer swings to –ve because of the change in flux, which is growing, generating a back emf in the/ a magnetic field in the secondary coil which opposes the change. Galvanometer finally swings back to zero because the flux, if any is stationary. Ammeter swings to zero Simultaneously the Galvanometer swings to +ve. Has a greater emf because the flux is rapidly changing/

##### Chapter 27 Lecture 24: Circuits: II HW 8 (problems): 26.10, 26.22, 26.35, 26.49, 27.12, 27.30, 27.40, 27.65 Due Friday, Nov.6.

elements being measured The current must pass directly through the ammeter Ammeter in a Circuit The ammeter is connected in series with the elements in which the current is to be measured Ideally, the ammeter should have zero resistance so the current being measured is not altered Ammeter from Galvanometer The galvanometer typically has a resistance of 60  To minimize the resistance, a shunt resistance, R p, is placed/

##### Chapter 27 Lecture 12: Circuits. Direct Current When the current in a circuit has a constant direction, the current is called direct current Most of the.

elements being measured The current must pass directly through the ammeter Ammeter in a Circuit The ammeter is connected in series with the elements in which the current is to be measured Ideally, the ammeter should have zero resistance so the current being measured is not altered Ammeter from Galvanometer The galvanometer typically has a resistance of 60  To minimize the resistance, a shunt resistance, R p, is placed/

##### Chapter 28B - EMF and Terminal P.D.

and its resistance must be small (negligible change in I). Digital read- out indicates current in A A E - + rg Ammeter has Internal rg The ammeter draws just enough current Ig to operate the meter; Vg = Ig rg Galvanometer: A Simple Ammeter The galvanometer uses torque created by small currents as a means to indicate electric current. 10 20 N S A current Ig causes the needle/

##### Measuring Devices.

there! If the electroscope drew any current, the leaves would fall back together again, just as the galvanometer compass needle returns to magnetic north the instant you take the wire from the battery. Thermal Heating Another phenomenon, sometimes useful /galvanometer. This method is useful when it is necessary to have a fast meter response time. The hot-wire and thermocouple effects are sometimes used to measure ac at high frequencies, in the range of hundreds of kilohertz up to tens of gigahertz. Ammeters/

##### ELECTRICAL AND ELECTRONINCS MEASUREMENTS.

it very sensitive to changes in the measured current frequency and it can be used as an accurate tuning device VIBRATION GALVANOMETER POWER FACTOR METER Power factor in an a.c. circuit just by dividing the power with product of current and voltage as these readings can be easily obtained from wattmeter, ammeter and voltmeter. Obviously there various limitations of using this method/

##### Electrical Components and Circuits By Naaimat Muhammed.

for full scale deflection, and in multiples of 10 between these extremes. Ammeters can be found with calibrated ranges of 1 micro-A for full scale deflection up to 1000 A for full scale deflection, and in multiples of 10 between these extremes. Voltmeter A voltmeter is a calibrated galvanometer with a series resistor so that the total resistance of the path is/

##### Presentation on Electrical measurements & measuring instruments.

pointer. 4 – The mirror reflects a beam of light on to a scale. This makes light-beam galvanometers sensitive to much lower current levels than pointer instruments – Current sensitivity galvanometer – Voltage sensitivity galvanometerGalvanometers are often employed to detect zero current or voltage in a circuit rather than to measure the actual level of current or voltage. 5 DC Ammeter – is always connected in series – low internal resistance – maximum/

##### 1 EMT 113: V-2008 School of Computer and Communication Engineering, UniMAP Prepared By: Prepared By: Amir Razif b. Jamil Abdullah DC Meter. CHAPTER 4.

field which will deflect the needle from pointing in the direction of earths magnetic field. An antique string galvanometer is shown in Figure 4.1.  The term "galvanometer" usually refers to any design of electromagnetic meter movement built for exceptional sensitivity, and not necessarily a crude device such as / as R a = R sh – (R b + R c )  The current I is the maximum current for the range on which the ammeter is set. The resistor R c can be determined from R c = I m (R sh + R m )/I 3  The resistor R /

##### AL Current Electricity P.66 Current = rate of flow of charge through cross-sectional area I = d Q / d t I = 1 C / 1 s = 1 C s -1 = 1 A One coulomb is.

0.9) (R 1 +1) = 1 R 1 = 1/9 P.84 For this conversion, a multiplier (high resistance) should be connected in series with the galvanometer to share most of the input voltage. 5 = (100μ)(1k + R M ) 5 = (100μ)(R total ) R total = 50 kΩ P.85 True reading / Y to point C P.92 Calibrating a voltmeter Read the reading of point C Voltmeter reading should be the same, otherwise Adjust the value of rheostat until the reading of galvanometer is zero P.93 Calibrating an ammeter Read the reading of point C Ammeter reading /