This is a question our experts keep getting from time to time. Now, we have got the complete detailed explanation and answer for everyone, who is interested!
A hint: the galvanometer will display zero deflection when the resistances of both the left and right sides of the instrument are identical to one another. To put it another way, the galvanometer will display zero deflection when there is no current flowing through it.
When there is no deflection shown on the galvanometer, what happens?
The galvanometer does not display any deflection when the magnet is kept in a fixed position… This demonstrates that a current is produced in the coil whenever there is motion that is relative to the magnet and occurs between the coil and the magnet.
The galvanometer will read zero deflection when the bridge is in a balanced position. Why?
When there is no current flowing through the coil or when the potential difference across the galvanometer is equal to zero, the bridge is said to be in a balanced condition. This condition takes place when the potential difference across the a to b and a to d connections are equal, while the potential difference across the b to c and c to d connections remains the same.
If the galvanometer in the given metre bridge arrangement exhibits no deflection at all, what should we assume the value of the unknown resistance R to be?
The value of the unidentified resistance, R, is determined to be 220.
While using a moving coil galvanometer, under what circumstances may one expect to acquire a stable deflection?
The magnetic torque that is produced in this manner causes rotation of the coil, which in turn causes twisting of the phosphor bronze strip. A constant angular deflection is achieved as a consequence of the spring S that is coupled to the coil because it generates a counter torque, also known as a restoring torque, k.
When the galvanometer in the image does not display any deflection, the amount of current (in amperes) that is flowing through
41 relevant questions found
What does it mean when the reading on a galvanometer is zero?
emfx = Rx, where Rx is the resistance of the piece of wire up to the contact point, when the galvanometer reads zero. Since that there is no flow of current via the galvanometer, there is also no flow of current through the unknown emf; hence, emfx can be directly measured.
When the galvanometer displays a reading of zero, what does this mean?
Adjusting R3 until the galvanometer’s reading is zero requires the presence of the unidentified resistance Rx in the circuit. As a result, there is no difference in potential between places b and d, which indicates that b and d are both located at the same potential. Because there is no current flowing through the galvanometer, this component of the circuit has no impact on the other components.
What is the reading in the galvanometer when there is no resistance connected across it? Why is this important to know?
A galvanometer that is linked in the circuit will not produce a reading at all.
What is the purpose of using resistance in series with galvanometer does it affect the null point?
* It is a procedure that does nothing. Hence, the null point is unaffected by either the internal resistance of the cell or the resistance of the galvanometer… Because this approach does not include any measurements of current or potential difference, the resistances of ammeters and voltmeters do not have any impact on the results of the measurements.
When the radius of the wire is tripled, what kind of an effect does that have on the null deflection of the galvanometer?
The null deflection of the galvanometer does not rely on the radius of the wire, as we may deduce from this fact. Hence, there will be no change in the null deflection of the galvanometer even if the radius of the wire is increased by a factor of three.
What is the function of the galvanometer?
A galvanometer is an device that deflects a moving coil to measure a small electrical current or a function of the current. This measurement is done by the galvanometer.
What kind of an effect does it have on the zero point when resistance is added in series with the galvanometer?
The null point is unaffected by the resistance that is connected in series with the galvanometer.
Why is it that the potentiometer provides more accurate readings than the voltmeter?
When measuring the electromotive force (emf) of a cell, a potentiometer is preferable over a voltmeter. This is due to the fact that a potentiometer is a null device and hence does not drain any current. In order to achieve a more accurate reading of the emf, a potentiometer is recommended over a voltmeter. This is due to the reason stated above.
When the key is in the locked position, what should the readings of the ammeter and voltmeter be?
The reading on the ammeter is going to be 0.24 amperes, and the value on the voltmeter is going to be 2.88 volts. Because an ammeter has almost little resistance and a voltmeter has almost no resistance at all, the voltage drop across both of them is effectively negligible.
Why isn’t the galvanometer just used straight up as an ammeter?
The galvanometer is a gadget that has a high degree of sensitivity. Because of this, it is possible for it to become destroyed whenever a significant current is carried through the galvanometer… Because the galvanometer has a higher resistance than the ammeter, adding it to the circuit in series will make it so that there is less current going through the whole thing.
Why is the galvanometer connected in series with the other components of the circuit?
The amount of current that is flowing through the coil has a direct relationship to how much it is bending. By connecting the resistance in parallel with the circuit, the galvanometer can be transformed into an ammeter…. In order to get an accurate reading of the current flowing through the circuit, it is linked in series with the circuit.
What is the resistance of the linked galvanometer after it has been transformed into an ammeter?
In order to transform a galvanometer into an ammeter, a parallel connection is made between the galvanometer and a extremely low resistance that is referred to as a “shunt” resistance. The value of the shunt is adjusted in such a way that it allows the majority of the current to flow through it.
Why is it necessary for there to be no flow of current through the galvanometer?
Because elements of a circuit that are connected in parallel have the same voltage across them, it follows that (1) and (2) continue to be true. As a result, we can draw the conclusion that, because there is only one solution to a circuit problem, the current that flows through the wire and the current that flows through the open circuit must be equal, which means that the current that flows through the wire is zero.
What are the conditions that must be met for there to be no current passing through the galvanometer?
There will be no flow of current through the galvanometer when the bridge is in a balanced condition. This is because the potential difference between the two ends of the galvanometer will be the same.
What are some of the other functions that a potentiometer serves?
They are utilized for correctly measuring voltage and for assisting in the production of variable voltage from a source of fixed voltage. Because they are passive devices, they do not require a power supply or any other circuits in order to perform their functions.
Does the potentiometer have a resistance that is infinite?
When we measure the emf of a cell using a potentiometer, the cell is considered to be in an open circuit when it is in the zero-deflection condition since no current flows through the circuit at that point. In this sense, the potentiometer can be thought of as an ideal resistance meter with an infinite range.
What are some of the drawbacks of using a potentiometer?
- The operation is painfully slow.
- It has a poor level of precision.
- It has a low bandwidth capacity.
- If you are working with a linear potentiometer, you will need to exert a significant amount of force in order to move the sliding contact.
- When the wiper moves across the resistive element, there is a chance that friction and wear will occur owing to the motion of the wiper.
Why is it that potentiometers provide more accurate readings?
The voltage that needs to be measured is connected through a slide wire in a potentiometer, and a movable jockey that is also connected to a galvanometer and other circuit components… When compared to other approaches, the accuracy of measurement is improved due to the fact that the circuit is open (there is no current when the state is balanced).