FORCE

FORCE

1. Net Force

   • Combination of all forces
   • Determines whether an object moves moves and also direction
   • If force is in same direction, then the force gets added
     • If forces are in opposite direction, they combine by subtraction

2. Newton

   • Strength of a force is measured in SI Unit called Newton
   • Was named after Sir Isaac Newton

3. Balanced Force

   • The motion of the object is not changed
     • Net force is zero because equal forces are exerted in opposite directions

4. Unbalanced Force

   • It can cause an object to start, stop or change direction of an object in motion
     • It can result in a net force and cause change in an object's motion

5. Force is push or pull exerted upon an object

   • Force is described by its strength and which direction it acts
     • The formula to find force=mass*acceleration

6. Friction

   • The force that two surfaces exert on each other when they rub against each other
     • Strength of force of friction depends on how hard surfaces press against each other and the type of surface involved
       • Rough surface would result in more friction
   • Static Friction: Static friction is the friction that exists between a stationary object and the surface on which it's resting.
   • Sliding Friction: Sliding friction results when an object slides across a surface.
   • Rolling Friction: A Rolling friction is a resistive force that opposes the rolling motion of an object. Rolling friction occurs when a round object rolls around a surface.
   • Fluid Friction: Fluid friction is the friction between a solid object as it moves through a liquid or a gas

7. Gravity

   • Universal Gravitation states that force of gravity acts between all objects in the universe
   • A force that pulls objects towards each other
   • Mass and distance affect gravity
     • Mass is measure of amount of matter in an object. Its SI unit is kilogram.
   • Weight is a measure of the gravitational force exerted on an object. It is also force of gravity on a person or object at the surface of a planet.
   • In Free Fall, the force of gravity is unbalanced, so the object accelertes
   • Air Resistance is a force that is caused by air. The force acts in the opposite direction to an object moving through the air. It is a type of fluid friction
     • Terminal velocity is the greatest velocity a falling object reaches and is reached when the force of air resistance equals the weight of the object
   • Projectile motion is a form of motion in which an object or particle is thrown near the earth's surface, and it moves along a curved path under the action of gravity only. The only force of significance that acts on the object is gravity, which acts downward to cause a downward acceleration

8. Laws Of Motion

   • First Law: An object at rest stays at rest and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force
   • Second Law: The acceleration of an object as produced by a net force is directly proportional to the magnitude of the net force, in the same direction as the net force, and inversely proportional to the mass of the object.
   • Third Law: For every action, there is an equal and opposite reaction. The statement means that in every interaction, there is a pair of forces acting on the two interacting objects.