Physics

TThe study of matter, energy, and how they interact.

Inertia

The resistance of an object to change its motion.

Acceleration 

 The rate at which velocity changes over time (m/s²).

Force

 A push or pull acting on an object (measured in Newtons).

Mass

The amount of matter in an object (measured in kg).

Weight

The force of gravity on an object (Weight = Mass × Gravity).

Momentum

The quantity of motion (Momentum = Mass × Velocity).

Work

Force × Distance (measured in Joules); only done when movement occurs.

Power

 Work ÷ Time (measured in Watts); how fast work is done.

Newton (N)

The SI unit of force.

Direct & Inverse Proportions

Direct: one increases, the other increases. Inverse: one increases, the other decreases.

Velocity

 Speed in a specific direction.

Speed

Distance ÷ Time

Motion

 A change in position relative to a reference point

Rate of Change (Δ)

The change in a quantity over time, often used with speed or velocity

Scalar

 A quantity with only magnitude (e.g., speed, distance).

Vector

 A quantity with magnitude and direction (e.g., velocity, force).

Displacement

The straight-line distance and direction from start to finish.

Distance

The total path traveled

Acceleration Due to Gravity

Free-Falling Object

An object falling under the sole influence of gravity.

Friction

A force that resists motion between two touching surfaces.

Simple Machine

A device that changes the direction or magnitude of a force.

Pulley

A wheel with a rope used to lift objects.

Inclined Plane

A sloped surface used to raise objects.

Wheel and Axle

A larger wheel attached to a smaller axle.

Wedge

Two inclined planes that come to a point to split or cut.

Screw

 An inclined plane wrapped around a cylinder.

Lever

A bar that pivots on a fulcrum to lift loads.

Fulcrum

The fixed point a lever pivots around.

Input/Output on Machine

Input is the force or effort you apply; output is the force the machine exerts.

Three classes of levers:

1st Class: Fulcrum between input and output (e.g., seesaw).

2nd Class: Output between fulcrum and input (e.g., wheelbarrow).
3rd Class: Input between fulcrum and output (e.g., broom).
Mechanical Advantage: Output force ÷ Input force.

Calculations

1. Speed = Distance ÷ Time
   
   

   • Velocity = Displacement ÷ Time
     
     

   • Acceleration = (Final Velocity - Initial Velocity) ÷ Time
     
     

   • Force = Mass × Acceleration
     
     

   • Work = Force × Distance
     
     

   • Power = Work ÷ Time
     
     

Mechanical Advantage (MA) = Load ÷ Effort

How machines make work easier:

They reduce the amount of force needed, change direction of force, or increase distance or speed.

Manipulate physics equations:

Rearranging formulas (e.g., solving for time: if Speed = Distance ÷ Time, then Time = Distance ÷ Speed).

Newton’s 3 Laws of Motion:

1st Law (Inertia): Objects stay at rest or in motion unless acted on.
2nd Law: F = m × a.

3rd Law: For every action, there is an equal and opposite reaction.

Describe mass vs. weight:

• Mass is constant, measured in kg.
  
  

• Weight depends on gravity (Weight = Mass × Gravity).

Rube Goldberg

1883 - 1970

San Francisco

Known for designing overly complex machines to perform simple tasks

Isaac Newton

1643-1727

United Kingdom

Formulated the 3 Laws of Motion, calculus, and the law of universal gravitation.

Physics

The study of matter, energy, and how they interact.