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Basic of Physics includes the Force and motion with Formulas and the Units. Basic Physics also explains the types of Force and Motion. Here we can also explain about the relationships of the motion with Newton's second law of motion and the force of momentum, etc. What is Force? Force is a physical quantity that can change the motion or direction of a body. When a force is applied to a body, that body can speed up, slow down, stop, or change direction. Without a force, a body cannot move or change its motion. Example of force: When you push a door, you are applying a force to it to make it move. If you push harder, the door will open faster. Explanation: Your hand is applying a force to the door to change its state of rest into motion. Formula of Force: When we know the mass of an object and the acceleration it produces, we calculate force as follows: ForceMass×Speed Force m × a m Mass (in kilograms) a Speed (in meters per second squared) SI Unit of Force: The International Unit (SI Unit) of force is the Newton (N). 1 Newton the force that gives a 1 kilogram body an acceleration of 1 meter per second squared. What is Motion? Motion is a physical state in which a body changes its position over time. When a body changes its position relative to a starting point, it is said to be in motion. Example of Motion: For example, if a car is moving down the road, it is moving because it is changing its location over time. SI Unit of Motion: Motion does not have a specific SI unit, but is measured in units such as meter (m), meter/second (m/s), or meter/second² (m/s²), which are for distance, velocity, and acceleration. Formula of Force: velocitydisplacement / Time Types of Motion Linear Motion Definition: Linear motion is when an object moves in a straight line from one place to another. Example: A car moving straight on a highway. Rotational Motion Definition: Rotational motion is when an object spins or rotates around a fixed axis. Example: A ceiling fan spinning or the Earth rotating on its axis. Formula: Angular Displacement: θ ωt Angular Velocity: ω θ / t Angular Acceleration: α (ω - ω₀) / t θ ω₀t + 1/2αt² SI Units: Angular Displacement radian (rad) Angular Velocity radian/second (rad/s) Angular Acceleration radian/second² (rad/s²) Oscillatory Motion Definition: Oscillatory motion is when an object moves back and forth in a repeated path about a central point. Example: A pendulum swinging or a vibrating guitar string. Formula: Period: T 1 / f Frequency: f 1 / T Displacement: x A sin(ωt) or x A cos(ωt) SI Units: Period seconds (s) Frequency hertz (Hz) Displacement meter (m) Curvilinear Motion Definition: Curvilinear motion is when an object moves along a curved path. Example: A car turning around a bend or a roller coaster loop. Formula: There is no single formula, but motion equations apply along the curve: Speed distance/time Acceleration may have tangential and centripetal parts SI Units: Distance meter (m) Velocity m/s Acceleration m/s² Projectile Motion Definition: Projectile motion is when an object is thrown into the air and moves under gravity in a curved (parabolic) path. Example: A football kicked into the air or a stone thrown from a cliff. Formulas: Horizontal Range: R (u² sin 2θ) / g Maximum Height: H (u² sin²θ) / (2g) Time of Flight: T (2u sin θ) / g SI Units: Height/Range meter (m) Time seconds (s) Velocity m/s Acceleration due to gravity g 9.8 m/s² Uniform Motion Definition: Uniform motion is when an object moves at a constant speed in a straight line. Example: A train is moving with constant speed on a straight track. Formula: Speed distance/time No acceleration (a 0) SI Units Speed m/s Time s Distance m Non-uniform Motion Definition: Non-uniform motion is when an object moves with a changing speed or direction. Example: A car slowing down or speeding up in traffic. Formula: Acceleration (final velocity - initial velocity) / time Equations of Motion: 1. v u + at 2. s ut + ½at² 3. v² u² + 2as Where: v Final velocity (m/s) u Initial velocity (m/s) a Acceleration (m/s²) t Time (s) s Displacement (m) SI Units: Distance m Velocity m/s Acceleration m/s² Displacement Displacement is the shortest distance between the starting point and ending point of an object, along with its direction. Formula: No specific formula, but displacement is often denoted by:s vt (for constant velocity)or used in motion equations. SI Unit: Meter (m) Example: If a person walks 10 m east, their displacement is 10 m east (not the path covered, but straight-line direction). Velocity Velocity is the rate of change of displacement. It tells both the speed and direction of motion. Formula: v s / t (Where v velocity, s displacement, t time) SI Unit: Meter per second (m/s) Example: A car moving 100 meters north in 5 seconds has a velocity of 20 m/s north. Acceleration Acceleration is the rate of change of velocity over time. Formula: a (v - u) / t (Where v final velocity, u initial velocity, t time) SI Unit: Meter per second squared (m/s²) Example: If a bike speeds up from 0 to 30 m/s in 5 seconds, its acceleration is 6 m/s². Newton’s Second Law of Motion The force acting on an object is directly proportional to the rate of change of its momentum, and this change takes place in the direction of the applied force. Force mass × acceleration Formula: Fma Where: F Force m Mass a Acceleration SI Units: Force (F) Newton (N) Mass (m) Kilogram (kg) Acceleration (a) Meter per second squared (m/s²) Example: If you push a shopping cart, it accelerates. The heavier the cart, the more force is required. A football accelerates more when kicked harder. Newton’s Third Law of Motion For every action, there is an equal and opposite reaction. Explanation: If an object A exerts a force on object B, then object B exerts an equal and opposite force on object A. Formula: F_action – F_reaction Where: F_action Force applied by object A on object B F_reaction Equal and opposite force applied by object B on object A SI Unit: Newton (N) Example: When you jump off a boat, the boat moves backward. A gun recoils when a bullet is fired — the bullet moves forward, and the gun moves backward. Work Definition: Work is done when a force is applied to an object and the object moves in the direction of the force. Formula: WorkForce×Displacement Where: Force applied force Displacement how much the object moves θ\theta angle between force and displacement SI Unit: Joule (J) Example: If you push a box and it moves 2 meters forward, you are doing work. But if you push a wall and it doesn't move, no work is done. Energy Definition: Energy is the ability to do work. It exists in many forms like kinetic energy (due to motion) and potential energy (due to position). Types of Energy: a. Kinetic Energy Energy of a moving object. Formula: KE (1/2) × m × v² Where: (m mass, v velocity) KE Kinetic Energy (in joules, J) m Mass of the object (in kilograms, kg) v Velocity of the object (in meters per second, m/s) b. Potential Energy Energy is stored due to height or position. Formula: PEmgh (m mass, g gravity, h height) SI Unit: Joule (J) Example: A moving car has kinetic energy. A book on a shelf has potential energy. Power Definition: Power is the rate at which work is done or energy is transferred. Formula: Power Work / Time Where: Power Rate at which work is done (in watts, W) Work Work done or energy transferred (in joules, J) Time Time taken (in seconds, s) Projectile Motion Projectile motion is the curved path followed by an object thrown or projected into the air under the force of gravity. Key Points: It has two motions at the same time: Horizontal (constant velocity) Vertical (acceleration due to gravity) Horizontal Range (R): R (v² × sin(2θ)) / g Maximum Height (H): H (v² × sin²(θ)) / (2g) Where: R Horizontal range (in meters) H Maximum height (in meters) v Initial velocity (in meters per second, m/s) θ Angle of projection (in degrees or radians) g Acceleration due to gravity (≈ 9.8 m/s²) Time of flight (T): T (2v × sin(θ)) / g Where: T Time of flight (in seconds) v Initial velocity (in meters per second, m/s) θ Angle of projection (in degrees or radians) g Acceleration due to gravity (≈ 9.8 m/s²) SI Units: Time seconds (s) Distance meter (m) Example: Throwing a ball, firing a cannonball, or jumping off a diving board — all follow projectile motion. Friction Definition: Friction is a force that opposes motion between two surfaces that are in contact. Formula: f μ × N Where: f Frictional force (in Newtons, N) μ Coefficient of friction (unitless) N Normal force (in Newtons, N) SI Unit: Newton (N) Types of Friction: Static friction (before motion) Kinetic friction (during motion) Rolling friction (like wheels) Example: You need to push harder to slide a box on the floor due to friction. Friction allows us to walk without slipping.

Basic Of Physics Force and Motion – Definitions, Formulas, and Examples

Physics Measurement System – SI Units, Torque, Power & Energy Simplified