Grade 8
  1. Introduction to Physics  1.1. What is physics and its scope?  1.2. Applications of Physics in Advanced Technology  1.3. The role of experiments in physics  1.4. Physics in Engineering and Medicine  1.5. The scientific method and its refinements  1.6. Emerging areas in physics
  2. Measurement and units  2.1. Advanced Physical Quantities and Their Classification  2.2. SI units and standardized measurement systems  2.3. Precision instruments for length and mass measurement  2.4. Advanced Techniques in Time Measurement  2.5. Calculating Volume Using Mathematical Formulas  2.6. Density measurement and applications  2.7. Temperature measurement with thermometers and sensors  2.8. Error analysis and minimization of systematic errors  2.9. Estimation, Approximation and Scientific Notation
  3. Kinematics and dynamics  3.1. Motion and its types – rectilinear, circular and oscillatory  3.2. Difference between distance and displacement  3.3. Speed vs Velocity – Understanding their Difference  3.4. Acceleration and its real life applications  3.5. Graphical Analysis of Motion - Interpreting Motion Graphs  3.6. Equations of motion - derivation and applications  3.7. Free fall and gravitational acceleration  3.8. Effect of air resistance on falling objects
  4. Force and Newton's laws of motion  4.1. Introduction to forces and their effects  4.2. Balanced and unbalanced forces - their role in motion  4.3. Newton's First Law - Understanding Inertia  4.4. Newton's Second Law - Mathematical Applications in Acceleration  4.5. Newton's Third Law - Action and Reaction Forces in Daily Life  4.6. Friction - its types, effects and methods of reduction  4.7. Circular motion and centripetal force  4.8. Impulse and Momentum – Real Life Examples  4.9. Application of Newton's laws in automobiles and space travel
  5. Work, Energy and Power  5.1. The concept of work and its mathematical representation  5.2. Energy and its forms – kinetic, potential, mechanical and internal  5.3. Understanding the Work-Energy Theorem  5.4. Law of Conservation of Energy – Practical Applications  5.5. Power and its units - how it differs from energy  5.6. Methods for improving the efficiency of machines and reducing energy losses  5.7. Applications of renewable and non-renewable energy in daily life
  6. Pressure and its applications  6.1. Understanding pressure in solids  6.2. Pressure in Fluids - Pascal's Principle  6.3. Atmospheric pressure and barometer  6.4. Buoyancy and Archimedes' principle  6.5. Hydraulics and its applications  6.6. Variations in pressure at depth and in high-altitude environments
  7. Heat and temperature  7.1. Heat as a form of energy  7.2. Temperature measurement using advanced sensors  7.3. Thermal expansion of solids, liquids and gases  7.4. Specific heat capacity and its applications  7.5. Heat transfer - conduction, convection and radiation  7.6. Latent heat and phase changes of matter  7.7. Thermal balance and heat exchange in everyday life
  8. Lighting and Optics  8.1. Nature of light - wave and particle theory  8.2. Reflection - laws and applications in optical instruments  8.3. Refraction and Snell's Law  8.4. Lenses - Uses in Image Formation and Corrective Lenses  8.5. Optical instruments – microscope, telescope and camera  8.6. Dispersion of light and colour formation  8.7. Total internal reflection - fibre optics and mirage creation  8.8. Human Eye and Vision Defects - Nearsightedness, Farsightedness and Astigmatism
  9. Sound and waves  9.1. Wave motion - characteristics and classification  9.2. Properties of sound - speed, pitch and intensity  9.3. Reflection and absorption of sound – echo and reverberation  9.4. Doppler effect and its applications  9.5. Ultrasound and sonography in medicine  9.6. Noise pollution and its prevention
  10. Electricity and Magnetism  10.1. Static electricity and electric charge  10.2. Electric current - conductors and insulators  10.3. Ohm's Law and Resistance  10.4. Series and Parallel Circuits – Differences and Applications  10.5. Electrical power and energy calculations  10.6. Safety measures in handling electricity  10.7. Magnetism - Properties and Field Lines  10.8. Electromagnetic Induction - Faraday's Law and Applications  10.9. Transformers and their use in electric power distribution
  11. Space science and universe  11.1. Solar System - Formation and Components  11.2. The Sun - structure, energy production and solar flares  11.3. Moon - effect of its gravity on the Earth  11.4. Eclipses – Solar and Lunar  11.5. Planets - Structure, Atmosphere and Moons  11.6. Satellites - artificial and natural  11.7. Gravity in space and its effect on astronauts  11.8. Theories of black holes and the expanding universe  11.9. Space Exploration - Rockets, Rovers and Space Stations
  12. Nuclear physics and modern applications  12.1. Structure of atom - protons, neutrons and electrons  12.2. Radioactivity - types and sources  12.3. Half-life and radioactive decay  12.4. The use of radioisotopes in medicine and industry  12.5. Nuclear fission and fusion – electricity generation
  13. Environmental Physics  13.1. Impact of energy consumption on the environment  13.2. Global warming and climate change - physics perspective  13.3. Sustainable energy – solar, wind and hydroelectric power  13.4. Role of Physics in Weather Forecasting  13.5. Physics of Natural Disasters - Earthquakes, Tsunamis and Tornadoes

Grade 8 → Electricity and Magnetism ↓


Series and Parallel Circuits – Differences and Applications


Introduction to circuit basics

In electricity and magnetism, circuits are the pathways that allow electricity to flow. They can be as simple as a single light bulb powered by a battery, or as complex as a home's electrical wiring. The two fundamental types of circuits are series circuits and parallel circuits. Understanding these two types helps us understand how electrical devices work and how electricity can be managed safely and efficiently.

What is a series circuit?

A series circuit is a circuit in which all the components are connected end-to-end in the same path for the electric current to follow. This means that the same current flows through each component in the circuit. Imagine a wire loop with other components such as bulbs, resistors or several devices placed along the loop.

The most important aspect of a series circuit is that if any component in the path gets disconnected, the circuit will break and no current will flow in the circuit.

Visual example of a series circuit

Features of series circuit

  • The current is the same in all components.
  • The total resistance of a circuit is the sum of the resistances of the individual components.
  • The voltage in a circuit is the sum of the voltages across each component.
  • If one component fails the whole circuit stops working.

Examples of formulas in series circuits

To calculate the total resistance (R), you can use the formula:

R_total = R_1 + R_2 + R_3 + ... + R_n

If you want to find the total voltage (V) in a series circuit, apply:

V_total = V_1 + V_2 + V_3 + ... + V_n

Applications of series circuits

Series circuits are often used in simple applications where power demands are not a major concern. For example:

  • Flashlights: Often use series circuits because they can simplify the design and ensure that the current is the same to all the bulbs.
  • Christmas lights: Older strings of Christmas lights are a good example where the bulbs are in series. If one bulb goes out, the whole string goes dark. Newer designs avoid this by incorporating a shunt.

What is a parallel circuit?

In parallel circuits, components are connected at common points or junctions, creating multiple paths for electricity to flow. Unlike series circuits, if one path is interrupted, current can still flow through the other paths, allowing devices in those paths to continue working.

Visual example of a parallel circuit

Features of parallel circuit

  • The voltage across each component is the same.
  • The total resistance becomes less than the individual resistances.
  • If one component fails, the other components can continue to work.

Examples of formulas in parallel circuits

To calculate the total resistance in a parallel circuit:

1/R_total = 1/R_1 + 1/R_2 + 1/R_3 + ... + 1/R_n

Similar to a series circuit, the formula for the total current (I) passing through the circuit is:

I_total = I_1 + I_2 + I_3 + ... + I_n

Applications of parallel circuits

Parallel circuits are used more in everyday electrical equipment due to their versatility and reliability.

  • Home wiring: Nearly all home electrical wiring is parallel, allowing different devices to work independently. If one path (or device) breaks, it does not affect the others.
  • Cars: Modern vehicles use parallel circuits for the electrical system so that all components can function independently.

Comparison of series and parallel circuits

Understanding the main differences between series and parallel circuits helps in selecting the right type of circuit for different applications.

Visual comparison of series vs parallel

Series Circuit Parallel Circuit

Summary of differences

Speciality Series Circuit Parallel Circuit
Current Same through all components Divided into different paths
Voltage Divided between components Same in all components
Resistance The total is the sum of the individual resistances Total number is less than any branch
If a component fails, The whole circuit closes Others can keep working

Conclusion

Both series and parallel circuits play important roles in wiring systems, electronics, and electrical gadgets. By choosing the appropriate circuit type, engineers can design a system that meets specific requirements, ensures safety, and optimizes energy use. Whether you're wiring a simple DIY project or working on developing a larger system, understanding these circuits is fundamental in electronics and electrical engineering.

As you learn more about electricity and magnetism, keep experimenting with different circuits so you can see first-hand how they work and how they differ. This practical experience will not only strengthen your understanding but also prepare you for more advanced electrical and electronic studies.


Grade 8 → 10.4


U
username
0%
completed in Grade 8

← Prev (10.3)
Ohm's Law and Resistance
Next (10.5) →
Electrical power and energy calculations

Comments 



Series and Parallel Circuits – Differences and Applications

https://www.physicsflow.com/g8/10.4?pfal=en