Advertisements
Advertisements
प्रश्न
Consider the potentiometer circuit as arranged in the figure. The potentiometer wire is 600 cm long. (a) At what distance from the point A should the jockey touch the wire to get zero deflection in the galvanometer? (b) If the jockey touches the wire at a distance of 560 cm from A, what will be the current in the galvanometer?
Advertisements
उत्तर
Let X be the null point on the wire at a distance x cm from point A, as shown.
Given:-
Total resistance of the wire AB = 15r
Resistance per unit cm = \[\frac{15r}{600}\]
Resistance of x cm of the wire = \[\frac{15rx}{600}\]
Resistance of (600 - x ) cm of the wire = \[\frac{15r\left( 600 - x \right)}{600}\]
(a) Applying KVL in loop 1, we get:-
\[\left( i_1 + i_2 \right)\frac{15}{600}rx + \frac{15}{600}r\left( 600 - x \right) i_1 + i_1 r = \epsilon...........(1)\]
Applying KVL in loop 2, we get:-
\[i_2 r + \frac{15}{600}rx \left( i_1 + i_2 \right) = \frac{\epsilon}{2}............(2)\]
For zero deflection in the galvanometer, i2 = 0. From equation (2),
\[\frac{15}{600}rx\left( i_1 \right) = \frac{\epsilon}{2}\]
\[ \Rightarrow i_1 = \frac{20\epsilon}{rx}\]
Substituting the values of i1 and i2 in equation (1), we get:-
x = 320 cm
(b) Putting x = 560 cm and solving equations (1) and (2), we get:-
\[i_2 = \frac{3\epsilon}{22r}\]
APPEARS IN
संबंधित प्रश्न
Kirchhoff's voltage law and current law are respectively in accordance with the conservation of .................................. .
- charge and momentum
- charge and energy
- energy and charge
- energy and momentum
Kirchhoff's junction law is equivalent to .............................
(a) conservation of energy.
(b) conservation of charge
(c) conservation of electric potential
(d) conservation of electric flux
State the two Kirchhoff’s rules used in electric networks. How are there rules justified?
Determine the current drawn from a 12 V supply with internal resistance 0.5 Ω by the infinite network shown in the figure. Each resistor has 1 Ω resistance.
State Kirchhoff's rules and explain on what basis they are justified.
Given the resistances of 1 Ω, 2 Ω, 3 Ω, how will be combine them to get an equivalent resistance of (11/5) Ω?
Given the resistances of 1 Ω, 2 Ω, 3 Ω, how will be combine them to get an equivalent resistance of 6 Ω?
Given the resistances of 1 Ω, 2 Ω, 3 Ω, how will be combine them to get an equivalent resistance of (6/11) Ω?
Determine the equivalent resistance of networks shown in Fig.
Consider the circuit shown in the figure. Find (a) the current in the circuit (b) the potential drop across the 5 Ω resistor (c) the potential drop across the 10 Ω resistor (d) Answer the parts (a), (b) and (c) with reference to the figure.
Twelve wires, each of equal resistance r, are joined to form a cube, as shown in the figure. Find the equivalent resistance between the diagonally-opposite points a and f.
Find the equivalent resistances of the networks shown in the figure between the points a and b.
An infinite ladder is constructed with 1 Ω and 2 Ω resistors, as shown in the figure. (a) Find the effective resistance between the points A and B. (b) Find the current that passes through the 2 Ω resistor nearest to the battery.
In the circuit shown in the figure below, E1 and E2 are two cells having emfs 2 V and 3 V respectively, and negligible internal resistance. Applying Kirchhoff’s laws of electrical networks, find the values of currents l1 and I2.
Solve the following question.
Using Kirchhoff’s rules, calculate the current through the 40 Ω and 20 Ω resistors in the following circuit.
State Kirchhoff’s current rule.
State Kirchhoff ’s voltage rule.
State and explain Kirchhoff’s rules.
How the emf of two cells are compared using potentiometer?
A potentiometer wire has a length of 4 m and resistance of 20 Ω. It is connected in series with resistance of 2980 Ω and a cell of emf 4 V. Calculate the potential along the wire.
The Kirchhoff's second law (ΣiR = ΣE), where the symbols have their usual meanings, is based on ______.
Two cell of 1.25 V and 0.75 V are connected parallel. The effective voltage will be:-
The figure below shows current in a part of electric circuit. The current I is ______.
Kirchhoff s second law is based on the law of conservation of ______
Three resistors having resistances r1, r2 and r3 are connected as shown in the given circuit. The ratio `i_3/i_1` of currents in terms of resistances used in the circuit is:
In a meter bridge the point D is a neutral point (Figure).
- The meter bridge can have no other neutral point for this set of resistances.
- When the jockey contacts a point on meter wire left of D, current flows to B from the wire.
- When the jockey contacts a point on the meter wire to the right of D, current flows from B to the wire through galvanometer.
- When R is increased, the neutral point shifts to left.
What is the advantage of using thick metallic strips to join wires in a potentiometer?
Power P is to be delivered to a device via transmission cables having resistance RC. If V is the voltage across R and I the current through it, find the power wasted and how can it be reduced.
The circuit in figure shows two cells connected in opposition to each other. Cell E1 is of emf 6V and internal resistance 2Ω; the cell E2 is of emf 4V and internal resistance 8Ω. Find the potential difference between the points A and B.
Two cells of voltage 10V and 2V and internal resistances 10Ω and 5Ω respectively, are connected in parallel with the positive end of 10V battery connected to negative pole of 2V battery (Figure). Find the effective voltage and effective resistance of the combination.
State the two Kirchhoff’s rules used in the analysis of electric circuits and explain them.
Derive the equation of the balanced state in a Wheatstone bridge using Kirchhoff’s laws.
The value of current in the 6Ω resistance is ______.
A 6-volt battery is connected to the terminals of a three-metre-long wire of uniform thickness and resistance of 100 ohms. The difference of potential between two points on the wire separated by a distance of 50 cm will be ______.
