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In an analog induction type wattmeter the pressure coil is connected accross the voltage source.It is intentionally made to have a larger number of turns than the current coil so that it's impedence increases and it draws minimum current from the circuit; causing lesser error in the reading.
The pressure coil in a watt meter is designed with more turns than the current coil to ensure that it has a higher resistance and can handle the higher voltage generated by the circuit being measured. This allows the pressure coil to accurately measure the power consumed or generated by the circuit.
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How can the magnetic flux associated with coil or a closed circuit be changed?
A simple method for altering the magnetic flux would be to change the amount of current flowing in the coil or circuit. Generally speaking, more current, more magnetic flux, and vice versa.
What meter reads amps and volts?
A volt-ampere meter. You can read current in two basic ways. The harder but more accurate way is to break the line where you are measuring current and basically insert the meter into the line so all current flows through the meter. The other type is a "clamp on" meter where the meter has something like a claw that you open and encircle the wire you want to measure. You determine the current by induction. The current flowing through the wire induces a smaller current in a loop created by the clamp on device. You can only measure current in one wire at a time. For example, you couldn't just clamp over a lamp cord and read a correct current because you are encircling two wires and the current going in each direction cancel each other out.
Why are there more thumbtacks attached in electromagnet b as compared to electromagnet a?
I'm having a lot of trouble seeing the picture that goes along with this question in the book, so I'll have to take a wild guess based on no information. My guess is that electromagnet 'b' has more current flowing in its wire coil than electromagnet 'a' has. Another possibility is that the current through both coils is the same, but the coil of electromagnet 'b' is wound with more turns of wire than the coil of electromagnet 'a' is. It's just a guess. To be sure, I really need to see that picture.
Describe how a simple generator produces electric energy?
A simple generator uses electromagnetic induction to convert mechanical energy into electrical energy. It consists of a coil of wire that rotates within a magnetic field, causing electrons to move and generate an electric current. As the coil spins, it cuts through magnetic lines of force, inducing a voltage in the wire and generating electricity.
Which electric heater will yield the greater heat output a large resistance in the coil or a small resistance in the coil?
A small resistance in the coil will yield greater heat output in an electric heater. This is because a small resistance allows for a larger current to flow through the coil, which in turn generates more heat due to the increased power dissipation (P = I^2 * R).
Why the current coil of wattmeter has more thikness wire than pressure coil?
Current coil carries the current.
Why the the reading on the newton meter increases when a current passes through the coil?
because it becomes more magnetic therfore it the pull on the coil will increase
Why is the electric watt meter connected in series with the rest of the circuits in the house?
First of all, you are referring to an energy meter, not a wattmeter. A wattmeter measures power, in watts, whereas an energy meter reads energy, in watt hours (or, more specifically, kilowatt hours). The energy company bills you for energy, not power.Having said that, the connections each instrument are the same. In fact, there are two coils inside an energy meter: a current coil, and a voltage (or potential) coil. The current coil is connected in series with the load while the voltage coil is connected in parallel with the supply voltage.The current coil measures the in-phase component of the current drawn by your load, so that the instrument always reads the true power (multiplied by time -the function of the aluminium disc) of the load -i.e. not the apparent power or reactive power.
Why is it necessary to consider positive and negative terminals of the ammeter when you connect leads from it to the circuit?
When you are dealing with DC voltages polarity is very important. Inside the ammeter is a coil through which the circuit amperage flows. Inside this coil is connected a steel armature of the meter movement. The more current is applied through the coil, the more the steel of the meter movement is drawn into the coil and this in turn moves the needle on the face of the meter to move further up the scale. If the coil polarity is reversed the magnetic field in the coil is reversed and the steel armature is driven in reverse. So instead of the meter movement moving up the scale it is driven to the zero end of the meter scale and it hammers up against the stop pin on the scale face.
What is pressure coil capacitance?
The series resistance (swamping resistance and multiplier) in pressure coil circuit has many turns.So in addition to inductance seen before, there are inter-turn capacitance also.If this capacitance effect exceeds the inductance effect, a phase-shift in pressure coil current will cause an error.When pressure coil capacitance roughly equals the inductance, the errors cancel each other.In most cases the inductance is more than the capacitance and thus the shunting capacitor mentioned before will serve the purpose.
What happens when AC supply is given to transformer?
There are more than one thing going on here, So note the sequence.1) When ANY Current is supplied to a transformer, the current in the primary coil produces a magnetic field.2) If ANY coil of wire "Sees" a changing magnetic field, it will produce current in the wires of that coil.3) Now comes the magic. If the current in the primary coil is changing all the time, the magnetic field produced by it will always be changing and therefore, the secondary coil will always 'see/sense' a changing magnetic field, it will produce a current in its wires directly caused by that changing magnetic field.4) Now for the word 'Transformer'. If the number of coils in the secondary coil is more than the number of coils in the primary coil, the voltage produced in the secondary coil will be more than the voltage in the primary. In that way the voltage is 'Transformed' to a different value. Hence the name of this device is 'Transformer'CommentA changing magnetic field does not 'produce current' in the wires of a coil. It produces voltage, NOT current! Current will only appear when the coil is connected to a load!
What is the effect of moving into a coil of more loops?
Moving into a coil with more loops increases the magnetic flux linked with the coil, resulting in a higher induced electromotive force (emf) in the coil. This leads to a stronger current being induced in the coil due to Faraday's law of electromagnetic induction.
How can you strengthen an electromagnet?
You can strengthen an electromagnet by increasing the current passing through the coil, adding more turns to the coil, using a core material with high magnetic permeability, or by proper winding techniques to optimize magnetic field alignment.
Why should you put the meter on the negative side when measuring current?
A meter can be used both on the positive or negative side of a circuit when measuring current. The current going to a load should be equal to the current coming back from the load. When measuring DC current, make sure the meter should be more than adequete to be placed in series with the circuit. Otherwise, use a clamp-on meter.
Why is it more difficuilt to move a magnet into a coil of more loops that is connected to a resistor?
Moving a magnet into a coil with more loops induces a stronger magnetic field, which in turn generates a larger induced current in the coil due to Faraday's law of electromagnetic induction. This induced current creates a magnetic field that opposes the motion of the magnet, resulting in increased resistance to movement. The resistor connected to the coil dissipates this induced current as heat, further impeding the magnet's motion.
How can the magnetic flux associated with coil or a closed circuit be changed?
A simple method for altering the magnetic flux would be to change the amount of current flowing in the coil or circuit. Generally speaking, more current, more magnetic flux, and vice versa.
How can the strength of an electromagnet be increased or decreased?
the current from the battery controls the strength of the electromagnet. Adjusting the voltage will also adjust the current as will adjusting the resistance in accordance with Ohm's Law. Current= voltage/resistance
