Grade 11
  1. Mechanics  1.1. dynamics  1.1.1. Motion in one dimension  1.1.2. Motion in two and three dimensions  1.1.3. Displacement and Distance  1.1.4. Speed and Velocity  1.1.5. Acceleration and deceleration  1.1.6. Graphical analysis of motion  1.1.7. Equations of motion (advanced derivations)  1.1.8. Free fall and terminal velocity  1.1.9. Projectile motion  1.1.10. Relative velocity in one and two dimensions  1.1.11. Motion of a car on an inclined plane  1.2. Dynamics  1.2.1. Newton's laws of motion and their applications  1.2.2. Inertia and Newton's first law  1.2.3. Force and types of force  1.2.4. Static and kinetic friction  1.2.5. Circular motion and centripetal acceleration  1.2.6. Non-uniform circular motion  1.2.7. Banking of roads and curves  1.2.8. Momentum and Impulse  1.2.9. Conservation of momentum in one and two dimensions  1.2.10. Applications of Newton's Third Law  1.3. Work, Energy and Power  1.3.1. Work done by a constant and variable force  1.3.2. Work–energy theorem  1.3.3. Kinetic and potential energy  1.3.4. Gravitational and elastic potential energy  1.3.5. Conservation of mechanical energy  1.3.6. Power and instantaneous power  1.3.7. Efficiency of machines  1.3.8. Work done by conservative and non-conservative forces  1.4. Rotational motion  1.4.1. Torque and angular acceleration  1.4.2. Rotational equilibrium  1.4.3. Moment of inertia and its applications  1.4.4. Angular momentum and its conservation  1.4.5. Kinetic energy of rolling motion and rotation  1.4.6. Parallel and Perpendicular Axis Theorem  1.4.7. Dynamics of rotational motion
  2. Gravitational force  2.1. Universal gravitation  2.1.1. Newton's law of universal gravitation  2.1.2. Gravitational field and potential  2.1.3. Change in acceleration due to gravity  2.1.4. Kepler's laws of planetary motion  2.1.5. Orbital mechanics and satellites  2.1.6. Escape velocity and orbital velocity  2.1.7. Weightlessness and free fall  2.1.8. Gravitational potential energy and energy in orbits  2.1.9. Black holes and gravitational lensing
  3. Properties of matter  3.1. Fluid mechanics  3.1.1. Density and pressure in liquids  3.1.2. Pascal's theory and applications  3.1.3. Archimedes' Principle and Buoyancy  3.1.4. Bernoulli's equation and applications  3.1.5. Continuity equation and the Venturi effect  3.1.6. Surface tension and capillarity  3.1.7. Viscosity and Poiseuille's Law  3.1.8. Reynolds number and turbulence  3.2. Elasticity and deformation  3.2.1. Hooke's law and the stress-strain relation  3.2.2. Elastic modulus and applications  3.2.3. Deformation and yield strength of solids
  4. Thermal physics  4.1. Heat and temperature  4.1.1. Thermometric properties and temperature scale  4.1.2. Thermal expansion of solids, liquids and gases  4.1.3. Heat transfer system  4.1.4. Specific heat capacity and calorimetry  4.1.5. Latent heat and phase change  4.2. Kinetic theory of gases  4.2.1. Molecular model of gases  4.2.2. Kinetic explanation of temperature  4.2.3. Ideal Gas Equation and Deviations  4.2.4. Mean free path and Maxwell–Boltzmann distribution  4.3. Laws of Thermodynamics  4.3.1. Zeroth Law and Thermal Equilibrium  4.3.2. First Law and Internal Energy  4.3.3. The Second Law and Entropy  4.3.4. Carnot cycle and heat engines  4.3.5. Refrigerators and heat pumps
  5. Waves and oscillations  5.1. Simple Harmonic Motion  5.1.1. Equations of SHM  5.1.2. Energy in SHM  5.1.3. Damped and forced oscillations  5.1.4. Resonance and applications  5.1.5. Pendulum and spring-mass system  5.2. Wave motion  5.2.1. Types of mechanical waves  5.2.2. Wave motion and energy transport  5.2.3. Superposition Principle and Standing Waves  5.2.4. Reflection, Refraction and Diffraction  5.2.5. Doppler effect in sound and light  5.2.6. Pulsations and interference
  6. Electricity and Magnetism  6.1. Electrostatics  6.1.1. Electric charge and conservation  6.1.2. Coulomb's law and its applications  6.1.3. Electric field and electric flux  6.1.4. Electric potential and potential energy  6.1.5. Capacitance and Energy Stored in a Capacitor  6.2. Current Electricity  6.2.1. Ohm's law and electrical resistance  6.2.2. Resistivity and temperature dependence  6.2.3. Kirchhoff's Laws and Circuit Analysis  6.2.4. Electrical power and efficiency  6.2.5. Combination of resistors  6.3. Magnetism and Electromagnetism  6.3.1. Magnetic fields and their sources  6.3.2. Magnetic force on moving charges  6.3.3. Electromagnetic induction  6.3.4. Faraday's and Lenz's laws  6.3.5. Inductance and Transformer  6.3.6. Alternating current and its applications
  7. Optics  7.1. Reflection and Refraction  7.1.1. laws of reflection and refraction  7.1.2. Mirrors and lenses  7.1.3. Total internal reflection and optical fiber  7.2. Wave optics  7.2.1. Interference and Diffraction  7.2.2. Young's double-slit experiment  7.2.3. Polarization of light
  8. Modern Physics  8.1.1. Photoelectric effect and Einstein's theory  8.1.2. Wave–particle duality  8.1.3. Heisenberg's uncertainty principle  8.1.4. Compton Effect  8.2. Atomic and Nuclear Physics  8.2.1. Atomic model and energy levels  8.2.2. Radioactive decay and half-life  8.2.3. Nuclear Fission and Fusion
  9. Electronics and Communication  9.1. Semiconductors  9.1.1. pn junction and diode  9.1.2. Transistors and Logic Gates  9.1.3. Integrated Circuits and Applications  9.2. Communication Systems  9.2.1. Basics of Analog and Digital Communication  9.2.2. Wireless and Optical Communication  9.2.3. Modulation and Demodulation

Grade 11 → Mechanics → Dynamics ↓


Newton's laws of motion and their applications


Newton's laws of motion are essential principles in the field of mechanics, a branch of physics. These laws describe the relationship between a body and the forces acting upon it. Isaac Newton formulated these laws in the late 17th century, and since then they have become fundamental to our understanding of motion and the mechanics of the things around us.

First law of motion: Law of inertia

The first law of motion states that an object at rest will remain at rest, and an object in motion will continue in motion unless an external force is applied. This concept is commonly known as inertia.

In simple terms, the first law states that things cannot start, stop, or change direction on their own. All changes in the motion of an object require a force.

For example, consider a book lying on a table. It will stay there until someone picks it up or an external force moves it. Similarly, a ball rolling on the floor will keep rolling until it hits an obstacle or slows down due to friction.

Let's illustrate this concept with a simple visual example using code to create a basic moving object that stops when it hits an invisible force such as friction:

Real-world applications

  • Seatbelts in cars are designed based on the first law. In a car accident, due to inertia, passengers continue their motion, but the seatbelts provide the external force necessary to hold them in place.
  • The concept of inertia is important in the motion of spacecraft, where there is no friction, so they continue moving in the same direction unless another force is applied.

Second law of motion: Law of acceleration

The second law of motion describes how the velocity of an object changes when an external force is applied to it. Mathematically, it is given as:

F = m * a

Where:

  • F is the applied force,
  • m is the mass of the object,
  • a is the acceleration produced.

This equation tells us that the force applied to an object is directly proportional to the acceleration of that object. The heavier the object (more mass), the more force is required to accelerate it.

Suppose a cart is being pushed along a straight path. If you apply a force, its acceleration depends on the mass of the cart. A heavier cart needs more force to achieve the same acceleration as a lighter cart.

Let's imagine this as a moving vehicle on which a force is acting:

Real-world applications

  • The second law of gravity is taken into account when calculating the fuel requirement for a rocket launch to overcome the Earth's gravity.
  • In engineering, this principle is used to design brakes in vehicles, which provide enough force to slow and stop the vehicle.

Third law of motion: Action and reaction

The third law of motion states that for every action there is an equal and opposite reaction. This means that forces always come in pairs.

If object A exerts a force on object B, then object B also exerts a force of equal magnitude and in the opposite direction on object A.

Consider the action of pushing against a wall. Your hands exert a force against the wall, and the wall exerts an equal and opposite force on your hands. Although the wall does not move, the forces are equal in strength and opposite in direction.

Let's represent this interaction with a simple visual pair of interacting forces:

Real-world applications

  • Rowing a boat involves pushing water backward with the oars (action), and this results in the boat moving forward (reaction).
  • In sports, when jumping from a diving board, the board pushes the diver backward, propelling him into the air.

Combining rules: Understanding momentum

Newton's laws are not just independent laws, but work together to explain various phenomena in mechanics. For example, in analyzing the motion of objects under various forces, it is important to use all three laws to determine the resultant motion.

Example: A box on a ramp

Imagine a box sliding down a ramp. The forces involved include gravity, friction, and the normal force from the surface of the ramp. By applying Newton's laws:

  • Use the first law to understand that without friction, the box would continue to accelerate indefinitely.
  • The second law helps in calculating acceleration considering forces such as gravity and friction.
  • The third law is obvious because the box exerts a force on the ramp while the ramp exerts an equal and opposite force on the box.

Conclusion

Newton's laws of motion provide essential insights into the mechanics of motion. They not only explain fundamental physics but also have important applications in engineering, technology, and everyday life. From simple tasks like playing sports to complex tasks like launching satellites, these laws remain integral to understanding and predicting the behavior of objects in motion.

These principles highlight the power of Newton's insights, guiding scientists and engineers in innovative ways to explore and interact with the physical world around us.


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Newton's laws of motion and their applications

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