Science

• Mass


  The amount of matter in a body
• Weight


  The force of gravity in a body
• Momentum


  The product of mass and gravity
• Friction


  The force between two objects against each other
• How to calculate momentum


  Momentum = m × v
• How to calculate pressure

  Pressure = density × gravity × height
• How to calculate weight

  Weight = mass × gravity
• Inertia


  The property of a mass which resists change from a state to rest or uniform motion
• How to calculate force

  F = MA
• How to calculate force from pressure

  F = P × A
• How to calculate velocity ratio in levers

  Effort distance / Load distance
• How to calculate gear ratio

  Number of teeth in load gear / Number of teeth in effort gear