Planar Motion Motion In A Plane
Concepts to Remember - JEE and CBSE Board Exams: Planar Motion - Motion in a Plane:
Vectors (Basic Definitions):
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Position Vector: Represents the position of a particle relative to a fixed origin in a coordinate system.
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Displacement Vector: Represents the change in position of a particle from its initial position to its final position.
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Velocity: Represents the rate of change of displacement of a particle with respect to time.
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Acceleration: Represents the rate of change of velocity of a particle with respect to time.
Equations of Motion:
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Equations of Motion in Vector Form: Provide the mathematical relations between acceleration, velocity, and displacement of a particle in motion.
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Equations of Motion in Scalar Form: Represent the components of acceleration, velocity, and displacement along specific coordinate axes.
Projectile Motion:
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Trajectory of a Projectile: The curved path followed by a projectile due to the combined effect of initial velocity and gravitational acceleration.
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Equations of Projectile Motion: Describe the motion of a projectile in terms of time of flight, maximum height, and range.
Uniform Circular Motion:
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Kinematic Equations of Uniform Circular Motion: Relate angular displacement, angular velocity, linear velocity, and radius of rotation.
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Centripetal Acceleration and Force: Explain the acceleration of an object moving in a circular path and the force required to produce this acceleration.
Tangential and Radial Components:
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Tangential and Radial Acceleration in Uniform Circular Motion: Describe the components of acceleration in uniform circular motion: tangential acceleration and radial acceleration.
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Components of Velocity and Acceleration: Express velocity and acceleration vectors into tangential and radial components.
Relative Motion:
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Concept of Relative Motion: Describes the motion of an object relative to another object in motion.
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Relative Velocity: Represents the velocity of an object relative to another object in motion.
Work, Energy, and Power:
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Concept of Work in 2D: Explains the concept of work done on a particle moving in a plane.
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Concept of Power: Represents the rate at which work is done or energy is transferred.
Impulse and Momentum:
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Impulse and Momentum in Vector Form: Provides mathematical relations between impulse, momentum, and force in vector form.
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Momentum Conservation Principle in 2D: States that the total momentum of a closed system remains constant in the absence of external forces.
Rotation:
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Angular Velocity and Displacement: Describe the angular motion of an object, relating angular displacement, angular velocity, and time.
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Angular Acceleration: Represents the rate of change of angular velocity with respect to time.
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Rotational Kinematics Equations: Relate angular displacement, angular velocity, angular acceleration, and time in rotational motion.
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Torque: Describes the force that causes an object to rotate around an axis, considering its moment arm.
Newton’s Laws of Motion:
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Newton’s First Law of Motion: States that an object at rest stays at rest, and an object in motion continues in motion with an unchanging velocity unless acted upon by an external force.
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Newton’s Second Law of Motion for Rotational Motion: Relates the net torque acting on an object to its angular acceleration.
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Newton’s Third Law of Motion for Rotational Motion: States that for every action-reaction pair, the torques produced are equal in magnitude but opposite in direction.
Friction:
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Static and Kinetic Friction: Describe the frictional force between two surfaces in contact, either at rest (static friction) or in motion (kinetic friction).
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Coefficient of Friction: Quantifies the resistance to motion between two surfaces.
Collision (1D and 2D):
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Elastic Collision in 1D: Describes a collision where both momentum and kinetic energy are conserved.
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Inelastic Collision in 1D: Describes a collision where only momentum is conserved, and kinetic energy is lost.
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Coefficient of Restitution: Measures the degree of elasticity in a collision.
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Oblique Collision in 2D: Describes a collision between two particles in two dimensions, considering both normal and tangential components.
Equilibrium of Forces:
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Concept of Equilibrium: Describes the state of an object where the net force acting on it is zero.
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Conditions of Equilibrium: Provide the criteria for an object to be in equilibrium in various situations.
Moment of Inertia:
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Concept of Moment of Inertia: Represents the resistance of an object to angular acceleration, analogous to mass in linear motion.
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Calculation of Moment of Inertia for Simple Bodies: Provides formulas to calculate the moment of inertia for simple objects like spheres, cylinders, and rods.
Parallel Axes Theorem:
- Parallel Axis Theorem for Moment of Inertia: Establishes a relation between the moment of inertia about an axis parallel to the axis passing through the center of mass.
Perpendicular Axis Theorem:
- Perpendicular Axis Theorem for Moment of Inertia: Relates the moments of inertia about two mutually perpendicular axes passing through a point.
Work-Energy Theorem:
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Concept of Work-Energy Theorem: States that the net work done on an object is equal to the change in its kinetic energy.
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Application to Motion in a Plane: Demonstrates the use of the work-energy theorem to solve problems involving motion in a plane.
Projectile Motion and Time of Flight:
- Time of Flight and Maximum Height in Projectile Motion: Derives equations to calculate the time of flight and maximum height reached by a projectile.
Centripetal Force and Newton’s Laws:
- Centripetal Force and its Relation to Newton’s Laws: Explains how Newton’s laws govern the motion of an object in circular motion, focusing on the centripetal force.
Rotational Motion and Inertia:
- Inertia in Rotational Motion: Highlights the role of inertia in resisting changes in rotational motion.
Moment of Inertia and Rotational Motion:
- Moment of Inertia and its Role in Rotational Motion: Explains how the moment of inertia affects the angular motion of an object.
Equilibrium and Rotational Motion:
- Equilibrium in Rotational Motion: Discusses the conditions for an object to be in rotational equilibrium.
Applications of Rotational Dynamics:
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Simple Pendulum: Analyzes the motion of a simple pendulum using rotational dynamics concepts.
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Physical Significance of Moment of Inertia: Explores the practical implications of the moment of inertia in various situations.