- In a series combination, the current has a single path, so the same current flows through each resistor.
- The equivalent resistance in a series combination is equal to the sum of the individual resistances, i.e. Rs = R1 + R2 + R3 + ....
Topics
Chemical Reactions and Equations
- Chemical Reactions in Daily Life
- Chemical Equations
- Balancing Chemical Equation
- Types of Chemical Reactions > Combination Reaction
- Types of Chemical Reactions > Decomposition Reaction
- Types of Chemical Reactions > Single Displacement Reaction
- Types of Chemical Reactions > Double Displacement Reaction
- Chemical Properties of Carbon Compounds > Oxidation
- The Effects of Oxidation Reactions in Everyday Life
Acids, Bases and Salts
- Acids and Bases in Daily Life
- Acids and Bases in the Laboratory
- Acids and Bases React with Metals
- Reaction of Metal Carbonates with Acids
- Acids and Bases Reaction with each other
- Reaction of Metallic Oxides with Acids
- Reaction of a Non-metallic Oxide with Base
- Common Properties of Acids and Bases
- The pH Scale
- Importance of pH in Everyday Life
- Salts > Family of Salts
- Salts > pH of Salts
- Salts > Chemicals from Common Salt
- Salts > Water in Salt Crystals
Metals and Non-metals
Carbon and its Compounds
- Importance of Carbon
- The Covalent Bond
- Allotropes of Carbon > Diamond
- Allotropes of Carbon > Graphite
- Allotropes of Carbon > Fullerene
- Carbon: A Versatile Element
- Organic Compounds
- Classification of Hydrocarbons
- Carbon Compounds: Chains, Branches, Rings
- Homologous Series
- Nomenclature
- Chemical Properties of Carbon Compounds > Combustion
- Ethanol
- Ethanoic Acid
- Soaps and Detergents
Life Processes
- Life Processes in Living Organisms
- Nutrition
- Autotrophic Nutrition
- Heterotrophic Nutrition
- Nutrition in Human Beings
- Dental Caries
- Cellular Respiration
- Human Respiratory System
- Production of ATP
- Blood Circulatory System
- Human Heart
- Blood Vessels Entering and Leaving The Heart
- Valves of the Heart
- Blood Pressure (B.P.)
- Blood Vessels
- Composition of Blood > Cellular Elements: Blood Platelets (Thrombocytes)
- Tissue Fluid (Or Intercellular Fluid)
- Lymph and Lymphatic System
- Transportation in Plants
- Transportation of Water
- Transportation of Food and Other Substances
- Excretion
- Excretion in Human Beings
- Kidney and Its Internal Structure
- Structure of a Kidney Tubule (Nephrons)
- Dialysis and Artificial Kidney
- Excretion in Plants
- Organ and Body Donation
Control and Co-ordination
- Human Nervous System
- Neuron (Or Nerve Cell)
- Synapse
- Nerves
- Reflex Action
- Reflex Arc
- The Human Brain
- The Spinal Cord
- Mechanism of Muscle Action Under Nervous Control
- Coordination and Response to Stimuli in Plants
- Tropic Movements in Plants
- Phototropism
- Geotropism
- Hydrotropism
- Thigmotropism
- Chemotropism
- Hormonal Regulation in Animals
How do Organisms Reproduce?
Heredity
Light – Reflection and Refraction
- Light and Its Straight-Line Propagation
- Reflection of Light
- Spherical Mirrors
- Image Formation by Spherical Mirrors
- Representation of Images Formed by Spherical Mirrors
- Image Formation by Concave Mirror
- Image Formation by a Convex Mirror
- Sign Convention for Reflection by Spherical Mirrors
- Ray Optics - Mirror Formula
- Refraction of Light
- Refraction through a Rectangular Glass Slab
- The Refractive Index
- Refraction by Spherical Lenses
- Image Formation by Lenses
- Image Formation in Lenses Using Ray Diagrams
- Sign Convention for Spherical Lenses
- Lens Formula
- Power of a Lens
The Human Eye and the Colourful World
- The Human Eye
- Defects of Vision and Their Correction
- Defects of Vision and Their Corrections > Myopia
- Defects of Vision and Their Corrections > Hypermetropia
- Defects of Vision and Their Corrections > Presbyopia
- Refraction of Light Through a Prism
- Dispersion of Light
- Atmosphere Refraction
- Scattering of Light
Electricity
Magnetic Effects of Electric Current
- Magnetic Effect of Electric Current
- Applications of Biot-Savart's Law > Magnetic Field due to a Finite Straight Current-Carrying Wire
- Magnetic Field Due to a Current-Carrying Conductor
- Right-hand Thumb Rule
- Applications of Biot-Savart's Law > Magnetic Field at the Centre of a Circular Loop
- Applications of Ampere’s Circuital Law > Magnetic Field of a Long Straight Solenoid
- Force on a Current Carrying Conductor in a Magnetic Field
- Fleming’s Left Hand Rule
- Magnetism in Medicine
- Domestic Electric Circuits
Our Environment
- Key Points: Series Combination of Resistors
Maharashtra State Board: Class 9
Resistors in Series:
When resistors are connected in such a way that their ends are joined one after the other in a single line, they are said to be connected in series. This arrangement is commonly used to increase the total resistance of a circuit.

Resistors in series
The same current (I) flows through all resistors in a series connection because there is only one current path. The value of current is I, and the potential difference between and is .
The three resistors, R1, R2, and R3, are connected in series in the circuit. If V1, V2, and V3 represent the potential differences of each resistor, R1, R2, and R3, respectively, then
V=V1+V2+V3−−−−−−−−(1)
If Rs ( for series) is the effective resistance between and , then, according to Ohm’s law:
V=IRs
V1=IR1, V2=IR2, V3=IR3
Substituting all these in equation (1), we get:
IRs = IR1 + IR2 + IR3
If resistors are connected in series, then:
Rs = R1 + R2 + R3 +⋯+ Rn
Maharashtra State Board: Class 9
Characteristics of Resistors Connected in Series:
- In a series connection of resistors, the same current flows through each resistor, as there is only one path for the current to travel.
- The effective resistance of the resistors is equal to the sum of their individual resistances, calculated as Rs = R1 + R2 + R3 +⋯+ Rn.
- The potential difference across the entire series arrangement is equal to the sum of the potential differences across each individual resistor.
- The effective resistance in a series connection is always greater than the resistance of any individual resistor.
- The primary purpose of this configuration is to increase the overall resistance in a circuit.
CISCE: Class 10



