Advertisements
Advertisements
Question
In the given circuit, assuming point A to be at zero potential, use Kirchhoff’s rules to determine the potential at point B.
Advertisements
Solution
According to Kirchhoff’s Junction Law, when applied at junction D:
Incoming current = outgoing current
So, 3A = 1A + current through 2Ω.
Hence, current through 2Ω is 2A from D to C. Applying Kirchhoff’s law to the loop containing R1, 2Ω and 4V.
3A is the current through R1 as the current coming out from the 4V battery is 3A.
4 = 3 × R1 + 2 × 2
⇒ R1 = 0 Ω
So, no potential drop between B and C.
Now lets analyse the bigger loop containing 4V, R and 2V (R1 can be omitted now); here the 4V and 2V are connected in series with B as a point between the two batteries. So we finally have the potential at B to be 2V.
APPEARS IN
RELATED QUESTIONS
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?
Given the resistances of 1 Ω, 2 Ω, 3 Ω, how will be combine them to get an equivalent resistance of (11/3) Ω?
Given the resistances of 1 Ω, 2 Ω, 3 Ω, how will be combine them to get an equivalent resistance of (11/5) Ω?
Determine the equivalent resistance of networks shown in Fig.
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.
A capacitor of capacitance 8.0 μF is connected to a battery of emf 6.0 V through a resistance of 24 Ω. Find the current in the circuit (a) just after the connections are made and (b) one time constant after the connections are made.
How the emf of two cells are compared using potentiometer?
Kirchhoff’s second law is a consequence of law of conservation of ______.
Figure shows current in a part of an electrical circuit. Then current I is ______.
Assertion: Kirchhoff’s junction rule follows from conservation of charge.
Reason: Kirchhoff’s loop rule follows from conservation of momentum.
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.
State the two Kirchhoff’s rules used in the analysis of electric circuits and explain them.
In the circuit shown in Figure below, E1 and E2 are batteries having emfs of 25V and 26V. They have an internal resistance of 1 Ω and 5 Ω respectively. Applying Kirchhoff’s laws of electrical networks, calculate the currents I1 and I2.
After a charge completes one full loop and returns to its starting point, what is the net change in potential?
Which sign convention is usually used for current leaving a junction?
At junction P, currents \[0.2\,\mathrm{A}\], \[0.6\,\mathrm{A}\], and \[0.7\,\mathrm{A}\] point towards P, while \[0.4\,\mathrm{A}\], \[0.5\,\mathrm{A}\], and \[I\] point away. What is the unknown current?
