Problem Solving Law Of Motion
Problem Solving Laws of Motion
Newton’s First law of motion: Inertia
 Inertia is the tendency of an object at rest to remain at rest, and an object in motion to continue moving at a constant velocity unless acted upon by an external force.
 Imagine trying to push a heavy object like a car; it won’t move easily due to its inertia.
Newton’s Second law of motion: Momentum and Force
 Momentum is the product of an object’s mass and velocity (p = mv). Force is any interaction that can change the motion of an object (F = ma).
 The greater the force applied to an object, the greater its acceleration, and the more massive an object, the smaller its acceleration when the same force is applied.
 This is evident when trying to push a light object vs a heavy object.
Newton’s Third Law of Motion: Action and Reaction
 For every action, there is an equal and opposite reaction.
 When one object exerts a force on another, the second object exerts a force of equal magnitude but opposite direction on the first object.
 For example, when you press on a wall, the wall pushes back on you with the same force.
Types of Forces:

Contact forces:
 Normal force: The force exerted by a surface perpendicular to the surface when an object is in contact with it.
 Friction: The force that opposes the motion of an object in contact with a surface.
 Tension: The force exerted by a string, rope, or cable when it is pulled tight.

NonContact forces:
 Gravitational force: The force of attraction between any two objects with mass.
 Electrostatic force: The force of attraction or repulsion between two charged particles.
 Magnetic force: The force of attraction or repulsion between two magnets or between a magnet and a magnetic material.
Equations of Motion:
 First equation of motion (V U = at)
 V represents the final velocity, U represents the initial velocity, a represents acceleration, and t represents time.
 Second equation of motion (S = Ut + ½ at²)
 S represents the displacement (distance moved in a specific direction), Ut represents the initial velocity multiplied by time, and ½ at² represents the additional distance covered due to acceleration.
 Third equation of motion ( V²  U² = 2aS)
 V represents the final velocity, U represents the initial velocity, a represents acceleration, and S represents displacement.
Special Cases of Motion:

Motion in a straight line: An object moves along a straight path without changing direction.

Motion on an inclined plane: An object moves on a surface that is not horizontal, such as a ramp or a hill.

Motion in a vertical circle: An object moves in a circular path, like a ball on a string.

Projectile motion: An object is launched into the air at an angle and moves only under gravity.
Conservation of Momentum
 Total momentum of a closed system remains constant, regardless of the internal forces within the system.
 useful when analyzing collisions and explosions.
Impulse:
 Impulse is the product of force and the time over which it is applied (I = Ft).
 A brief, large force can impart the same momentum change as a small force applied over a longer time.