Question
How to use Kirchhoff's rules ?
✓
Answer
→First, label currents in each resistor by symbol I and a directed arrow to indicate that a current flows along the resistor in the direction indicated.
→ If ultimately I is to be positive, the actual current in the resistor is in the direction of the arrow.
→ If I turns out to be negative, the current actually flows in a direction opposite to the arrow.
→ For each source (i.e cell or some other source of electrical power) the positive and negative terminals are labelled as well as a directed arrow with a symbol for the current flowing through the cell.
→The potential difference of the cell $V = V ( P )$ $- V ( N )=\varepsilon- I r$ which is between the positive terminal P and negative terminal N .
→If while labelling the current through the cell goes from P to N then $V =\varepsilon+ Ir$.
→ If ultimately I is to be positive, the actual current in the resistor is in the direction of the arrow.
→ If I turns out to be negative, the current actually flows in a direction opposite to the arrow.
→ For each source (i.e cell or some other source of electrical power) the positive and negative terminals are labelled as well as a directed arrow with a symbol for the current flowing through the cell.
→The potential difference of the cell $V = V ( P )$ $- V ( N )=\varepsilon- I r$ which is between the positive terminal P and negative terminal N .
→If while labelling the current through the cell goes from P to N then $V =\varepsilon+ Ir$.
Need a full question paper?
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.
Explore more
Similar questions
Arrange the following electromagnetic waves in the order of their increasing wavelength :
a. $\gamma$-rays
b. Microwaves
c. X-rays
d. Radio waves
How are infra-red waves produced? What role does infra-red radiation play in
i. maintaining the Earth's warmth and
ii. physical therapy?
→a. $\gamma$-rays
b. Microwaves
c. X-rays
d. Radio waves
How are infra-red waves produced? What role does infra-red radiation play in
i. maintaining the Earth's warmth and
ii. physical therapy?
The mass of an alpha particle located in a uniform electric field of $1.6 \times 10^5 V / m$ is $6.4 \times 10^{-27}$ Kg and charge is $3.2 \times 10^{-19} C$. What will be the velocity of the particle after travelling a path of $2 \times$ $10^{-2} m$ at rest?
→Explain the refraction by two transparent spherically curved surface.
If the radius of the nucleus of $Al ^{27}$ is 3.6 Fermi , then what will be the radius of the $Fe ^{125}$ nucleus?
→The north pole of a magnet is brought down along the axis of a horizontal circular coil. As a result, the flux through the coil changes from 0.35 weber to 0.86 weber in an interval of half a second. Find the average emf induced during this period. Is the induced current clockwise or anticlockwise as you look into the coil from the side of the magnet?
Can we measure the potential difference across an unbiased p–n junction by connecting a sensitive voltmeter across it?
Give examples where:
- The velocity of a particle is zero but its acceleration is not zero.
- The velocity is opposite in direction to the acceleration.
- The velocity is perpendicular to the acceleration.
Find the flux of the electric field through a spherical surface of radius R due to a charge of $10^{-7}$ C at the centre and another equal charge at a point 2R away from the centre.
→Calculate the mass of an $\alpha$-particle. Its binding energy is 28.2MeV.
→The refractive index of a material changes by 0.014 as the colour of the light changes from red to violet. A rectangular slab of height 2.00cm made of this material is placed on a newspaper. When viewed normally in yellow light, the letters appear 1.32cm below the top surface of the slab. Calculate the dispersive power of the material.