Physics: Inertia and Action-Reaction

Study Notes

Definition: Inertia is the tendency of an object to resist changes in its motion.
Law of Inertia: An object at rest will remain at rest, and an object in motion will continue to move with a constant velocity, unless acted upon by an external force.
Examples:
- A car maintaining its velocity on a straight road.
- A bowling ball keeping its motion on a smooth lane.

Definition: For every action, there is an equal and opposite reaction.
Examples:
- When you push a wall, the wall exerts an equal and opposite force on you.
- When a car accelerates, the ground exerts an equal and opposite force on the car.
Key point: Action and reaction forces are always paired, but they act on different objects.

Definition: Force is a push or pull that causes an object to change its motion.
Relationship between force and acceleration:
- Force (F) is proportional to acceleration (a).
- F = ma, where m is the mass of the object.
Examples:
- A heavy box requires more force to accelerate than a lighter box.
- A car accelerates faster when more force is applied to the gas pedal.

Definition: Friction is a force that opposes motion between two surfaces in contact.
Types of friction:
- Static friction: Prevents an object from moving.
- Kinetic friction: Slows down an object in motion.
Examples:
- Tires gripping the road to prevent slipping.
- Brakes slowing down a car.

Definition: Projectile motion is the motion of an object under the influence of gravity.
Key characteristics:
- Horizontal motion: Constant velocity.
- Vertical motion: Acceleration due to gravity (g = 9.8 m/s^2).
Examples:
- A thrown ball following a parabolic path.
- A launched rocket experiencing both horizontal and vertical motion.

Inertia is the tendency of an object to resist changes in its motion.
Objects at rest will remain at rest, and objects in motion will continue to move with a constant velocity, unless acted upon by an external force.
Examples of inertia include a car maintaining its velocity on a straight road and a bowling ball keeping its motion on a smooth lane.

For every action, there is an equal and opposite reaction.
Examples of action and reaction include pushing a wall and experiencing an equal and opposite force, and a car accelerating forward while the ground exerts an equal and opposite force backward.
Action and reaction forces are always paired, but they act on different objects.

Force is a push or pull that causes an object to change its motion.
Force is proportional to acceleration, and can be calculated using the equation F = ma, where m is the mass of the object.
More force is required to accelerate a heavier object, and increasing the force applied to an object can increase its acceleration.
Examples of force and acceleration include a heavy box requiring more force to move than a lighter box, and a car accelerating faster when more force is applied to the gas pedal.

Friction is a force that opposes motion between two surfaces in contact.
There are two types of friction: static friction, which prevents an object from moving, and kinetic friction, which slows down an object in motion.
Examples of friction include tires gripping the road to prevent slipping, and brakes slowing down a car.

Projectile motion is the motion of an object under the influence of gravity.
Objects in projectile motion have a constant horizontal velocity and an acceleration due to gravity (g = 9.8 m/s^2).
Examples of projectile motion include a thrown ball following a parabolic path, and a launched rocket experiencing both horizontal and vertical motion.