Grade 10
  1. Mechanics  1.1. Dynamics  1.1.1. Motion in one dimension  1.1.2. Motion in two dimensions  1.1.3. Displacement and Distance  1.1.4. Speed and Velocity  1.1.5. Acceleration  1.1.6. Graphical representation of motion  1.1.7. Equations of motion  1.1.8. Free fall and acceleration due to gravity  1.1.9. Projectile motion  1.1.10. Relative speed  1.2. Dynamics  1.2.1. Newton's Laws of Motion  1.2.2. Inertia and mass  1.2.3. Force and its types  1.2.4. action and reaction force  1.2.5. Friction and its effects  1.2.6. Coefficient of friction  1.2.7. Circular motion  1.2.8. Centripetal force and centripetal acceleration  1.2.9. Momentum and Impulse  1.2.10. Conservation of momentum  1.2.11. Newton's third law and applications  1.3. Work, Energy and Power  1.3.1. Work done by the force  1.3.2. Work–energy theorem  1.3.3. Kinetic energy  1.3.4. Potential energy  1.3.5. Mechanical energy  1.3.6. Energy Conservation  1.3.7. Power and efficiency  1.3.8. Renewable and non-renewable energy sources  1.4. Gravitational force  1.4.1. Newton's law of universal gravitation  1.4.2. Gravitational field and field strength  1.4.3. Acceleration due to gravity on different planets  1.4.4. Kepler's laws of planetary motion  1.4.5. Orbits and satellites  1.4.6. Weight and apparent weight  1.4.7. Gravitational potential energy
  2. Properties of matter  2.1. States of matter  2.1.1. Solid, liquid and gas  2.1.2. Molecular structure of matter  2.1.3. Intermolecular forces  2.1.4. Plasma and Bose–Einstein condensate  2.2. Pressure  2.2.1. Definition of Pressure  2.2.2. Pressure in liquids  2.2.3. Atmospheric pressure  2.2.4. Pascal's principle  2.2.5. Archimedes' Principle and Buoyancy  2.2.6. Surface tension and capillarity  2.3. Elasticity  2.3.1. Hooke's law  2.3.2. Stress and strain  2.3.3. Elastic Limit and Modulus of Elasticity  2.3.4. Applications of Elasticity
  3. Thermal physics  3.1. heat and temperature  3.1.1. Difference Between Heat and Temperature  3.1.2. Temperature scale  3.1.3. Thermal expansion  3.1.4. Thermal equilibrium  3.2. Heat transfer  3.2.1. Conductivity  3.2.2. Convection  3.2.3. Radiation  3.2.4. Insulation and its applications  3.3. Thermal properties of matter  3.3.1. Specific heat capacity  3.3.2. Latent heat and phase change  3.3.3. Boiling and Melting Point  3.3.4. Heat engines and refrigeration  3.4. Laws of Thermodynamics  3.4.1. Zeroth law of thermodynamics  3.4.2. First law of thermodynamics  3.4.3. Second law of thermodynamics  3.4.4. Carnot cycle
  4. Waves and optics  4.1. Nature and properties of waves  4.1.1. Types of waves in nature and properties of waves  4.1.2. Transverse and longitudinal waves  4.1.3. Wave parameters  4.1.4. Reflection and refraction of waves  4.1.5. Superposition and Interference  4.1.6. Standing Waves and Resonance  4.1.7. Doppler effect  4.2. Sound waves  4.2.1. Characteristics of sound waves  4.2.2. Speed of sound in different mediums  4.2.3. Applications of sound waves  4.2.4. Ultrasound and its uses  4.3. Light Waves and Optics  4.3.1. Nature of light  4.3.2. Reflection of light  4.3.3. Laws of reflection  4.3.4. Mirrors and Image Formation  4.3.5. Refraction of light  4.3.6. Snell's Law  4.3.7. Lenses and Image Formation  4.3.8. Total internal reflection and critical angle  4.3.9. Optical fibre  4.4. Optical Instruments  4.4.1. Microscope  4.4.2. Telescope  4.4.3. Human eye and vision defects  4.4.4. Camera and its working principle
  5. Electricity and Magnetism  5.1. Electrostatics  5.1.1. Electric charge and its properties  5.1.2. Conductors and Insulators  5.1.3. Coulomb's law  5.1.4. Electric field and field lines  5.1.5. Electric potential and potential difference  5.1.6. Capacitors and Capacitance  5.2. Current Electricity  5.2.1. Electric current and its measurement  5.2.2. Ohm's law  5.2.3. Resistance and resistivity  5.2.4. Series and Parallel Circuits  5.2.5. Electric power and energy  5.2.6. Kirchhoff's Laws  5.3. Magnetism and Electromagnetism  5.3.1. Magnetic field and field lines  5.3.2. Magnetic effects of electric current  5.3.3. Electromagnetic induction  5.3.4. Faraday's laws of electromagnetic induction  5.3.5. Transformers and Applications  5.3.6. AC and DC current
  6. Modern Physics  6.1. Nuclear physics  6.1.1. Structure of the atom  6.1.2. Bohr's atomic model  6.1.3. Electron Energy Levels  6.1.4. X-rays and applications  6.2. Radioactivity  6.2.1. Types of radiation  6.2.2. Half-life and radioactive decay  6.2.3. Nuclear reactions and applications  6.2.4. Fission and Fusion  6.3. Quantum physics  6.3.1. Wave–particle duality  6.3.2. Photoelectric effect  6.3.3. Energy quantization  6.3.4. Heisenberg's uncertainty principle
  7. Electronics and Communication  7.1. Semiconductors  7.1.1. Conductors, Insulators and Semiconductors  7.1.2. Diodes and their applications  7.1.3. Transistors and Logic Gates  7.1.4. LEDs and photodiodes  7.2. Communication Systems  7.2.1. Basics of communication  7.2.2. Analog and digital signals  7.2.3. Wireless and optical fibre communication  7.2.4. Radio Waves and Modulation

Grade 10 → Mechanics → Dynamics ↓


Friction and its effects


Friction is a force that opposes the motion of objects. In the study of dynamics in mechanics, understanding friction is important because it plays a vital role in countless real-world scenarios. Whether you are walking, driving a car or even writing with a pen, friction is at work. In this detailed discussion, we will explore what friction is, its types, and its many effects on everyday life.

What is friction?

Friction is a resistive force that occurs when two surfaces collide with each other. It acts in the opposite direction to the motion or attempted motion of the objects in contact. Friction is caused mainly by the roughness of the surfaces and the intermolecular forces between them. Even surfaces that appear smooth have microscopic bulges and valleys that cause friction.

Mathematically, friction can be described using the formula:

F_friction = μ * N

Where ( F_friction ) is the friction force, ( μ ) (mu) is the friction coefficient, and ( N ) is the normal force applied perpendicular to the surfaces in contact.

Types of friction

There are several types of friction, each with its own unique characteristics and effects. Understanding these can help us identify how they affect motion in different scenarios.

Static friction

Static friction is the friction force that prevents two surfaces from sliding past each other. It acts when an object is stationary, and it is necessary to overcome it to start motion. The force of static friction increases with the applied force until it reaches a maximum value, after which motion occurs. Static friction is usually greater than kinetic friction.

F_static ≤ μ_static * N
static friction

Kinetic friction

Kinetic friction, also known as sliding friction, occurs when an object is moving on a surface. Once static friction is overcome, kinetic friction comes into play. Its value is usually less than static friction, which is why moving objects tend to continue moving once they start.

F_kinetic = μ_kinetic * N
Kinetic friction

Rolling friction

Rolling friction is the resistance that occurs when an object rolls on a surface. This type of friction is usually much less than both static and kinetic friction, which explains why rolling a heavy object is easier than sliding it. Rolling friction is usually found in situations involving wheels, balls, or cylinders.

Fluid friction

Fluid friction occurs when an object moves through a fluid, which can be a liquid or a gas. Air resistance is a form of fluid friction. This type of friction depends on the speed of the object as well as the properties of the fluid. Generally, fluid friction increases with the speed of the object moving through the fluid.

Effects of friction

Friction affects motion in several important ways. Although it is often seen as an obstacle to motion, friction is also essential for a variety of activities. Below are some important effects of friction:

Friction as a barrier

In many cases, friction acts as a barrier to motion. For example, a car engine has to overcome friction within the engine and between the tires and the road surface. This results in energy losses, making engines less efficient.

Another visual example can be seen with sliding blocks:

Direction of friction

Friction is an essential force

Friction is important for many everyday activities. Walking would be impossible without friction because it provides the grip our feet need to push against the ground. Similarly, friction between vehicle tires and road surfaces helps cars move and stop safely.

Take the example of a pedestrian:

Walking

Breakdown

Friction causes materials to wear out. Machines wear out over time because of the constant friction between moving parts. To reduce this, lubricants are often used to reduce friction, increasing the longevity of mechanical components.

Reducing friction

There are various ways to reduce friction, increase efficiency and extend the life of tools and machinery:

Lubrication

Applying a lubricant such as oil or grease between surfaces reduces friction as it forms a thin layer that prevents direct contact. It is commonly used in machines and engines.

Smoothing the surfaces

Polishing can reduce friction by reducing the roughness of surfaces. When surfaces are smooth, there is less contact between the microscopic roughnesses.

Use of bearings

Bearings are placed to facilitate smooth movement between surfaces. By allowing rolling instead of sliding, bearings reduce friction substantially.

Increasing friction

In some situations, increasing friction is important to ensure safety and functionality:

Selection of material

Using materials with a higher friction coefficient can improve grip and stability. For example, selecting tire rubber designed for specific weather conditions can help maintain traction.

Texturing of surfaces

Adding texture to surfaces, such as tread on a tire or ridges on the sole of a shoe, increases friction, which helps prevent slipping.

Environmental modification

Changes to the environment, such as adding sand or salt to icy roads, can increase friction, increasing safety for vehicles and pedestrians.

Conclusion

Friction is a fundamental force that affects everyday life in many ways. It can both impede and enable motion, making it an important consideration in activities ranging from simple walking to complex machine operation. Understanding the nature of friction, its types, and how to manage its effects can lead to better designs and safer, more efficient systems.


Grade 10 → 1.2.5


U
username
0%
completed in Grade 10

← Prev (1.2.4)
action and reaction force
Next (1.2.6) →
Coefficient of friction

Comments 



Friction and its effects

https://www.physicsflow.com/g10/1.2.5?pfal=en