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प्रश्न
In Wheatstone’s meter-bridge experiment, the null point is obtained in the middle one-third portion of the wire. Why is it recommended?
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उत्तर
- Due to the non-uniformity of the bridge wire and the development of contact resistance at the wire's ends, the value of unknown resistance X may not be accurate.
- To reduce these errors, the value of R is modified so that the null point is found in the middle one-third of the wire (between 34 and 66 cm), resulting in the smallest and virtually identical percentage errors in the measurement of lx and lR.
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संबंधित प्रश्न
Obtain the balancing condition for the Wheatstone bridge arrangements as shown in Figure 4 below:
Choose the correct:
Four resistances 10 Ω, 10 Ω, 10 Ω and 15 Ω form a Wheatstone’s network. What shunt is required across 15 Ω resistor to balance the bridge
Four resistances 4 Ω, 8Ω, XΩ and 12Ω are connected in a series to form Wheatstone’s network. If the network is balanced, the value of X is ______.
Explain with a neat circuit diagram. How you will determine the unknown resistances using a meter bridge.
In a meter bridge, the balance point is found to be at 39.5 cm from the end A when the resistor R is 12.5 Ω (right gap).
a) Determine the resistance of X (left gap).
b) Determine the balance point of the bridge if X and R are interchanged?
c) What happens if the galvanometer and cell are interchanged at the balance point of the bridge?
The current which flows in a galvanometer of Wheatstone bridge is directly proportional to ______
In a metre bridge experiment, the null point is obtained at 20 cm from one end of the wire when resistance X is balanced against another resistance Y. If X < Y, then where will be the new position of the null point from the same end, if one decides to balance a resistance of 4X against Y?
In the circuit shown, a metre bridge is in its balanced state. The metre bridge wire has a resistance 0.1 ohm/cm. The value of unknown resistance X and the current drawn from the battery of negligible resistance are ____________.
The metre bridge works on the principle of ______.
On interchanging the resistances, the balance point of a metre bridge shifts to the left by 10 cm. The resistance of their series combination is 1 k`Omega`. How much was the resistance on the left slot before interchanging the resistances?
In Wheatstone's network p = 2 `Omega` , Q = 2 `Omega`, R = 2 `Omega` and S = 3 `Omega`. The resistance with which S is to be shunted in order that the bridge may be balanced is ______.
What is the e.m.f of the cell C in the circuit shown in figure, if the deflection in the galvanometer is zero, the resistance of the wire is 3 `Omega`, The length of the wire is 100 cm?
In the network shown cell E has internal resistance r and the galvanometer shows zero deflection. If the cell is replaced by a new cell of emf 2E and internal resistance 3r keeping everything else identical, then ______.
In the measurement of a resistance by the Wheatstone bridge, the known and the unknown resistance are interchanged to eliminate ____________.
ln, a Wheatstone network, P = Q = R = 8 `Omega` and S is 10 `Omega`. The required resistance to be connected to S so that network is balanced is ______.
The current through 1 `Omega` resistance in the following circuit is ______.
A resistance of 20 Ω is connected in the left gap of a meter bridge and an unknown resistance greater than 20 Ω is connected in the right gap. When these resistances are interchanged, the balance point shifts by 20 cm. The unknown resistance is ______.
The figure below shows a balanced Wheatstone network. If it is disturbed by changing P to 22Ω, then which of the following steps will bring the bridge again to a balanced state?
In the given circuit, if I = 100 mA and I1 = I4 = 60 mA, the currents I3 and I5 are ______.
With an unknown resistance X in the left gap and a resistance of 30 Ω of the gap of a metre bridge, the null point is obtained at 40 cm from the left end of the wire. Find the unknown resistance. Also, find the shift in the null point when resistance in each gap is shunted by a resistance of 8 Ω.
In the given Wheatstone's network, what should be the value of R for the network to be balanced?
Two resistances are connected in two gaps of a meter bridge. The null point is obtained at 20 cm from zero end. A resistance of 15 is connected in series with smaller of the two. The null point shifts to 40 cm. The smaller resistance used in is ______.
The current passing through the battery in the given circuit is:
A battery of 6 V is connected to the circuit as shown below. The current I drawn from the battery is:
