Physics⏲️📡💡

• Acceleration


  The rate of change of velocity
• Acceleration-Time Graph


  Plot showing how acceleration changes over a period of time. The area underneath the graph represents change in velocity. The gradient represents the rate of change of acceleration, called ‘jerk’
• Centre of Gravity


  The single point through which the object’s weight can be said to act
• Conservation of Energy

  Energy cannot be created or destroyed - it can only be transferred into different forms
• Conservation of Linear Momentum


  The total linear momentum of a system before an event must be equal to the total linear momentum of the system after the event, assuming no external forces act
• Coplanar Vectors


  Vectors which lie on the same plane
• Displacement-Time Graph

  Plots showing how displacement changes over a period of time. The gradient gives the velocity. Curved lines represent an acceleration
• Efficiency


  The ratio of useful energy output to total energy input for a given system
• Equilibrium


  For an object to be in equilibrium, both the resultant force and resultant moment acting on the object must be equal to zero
• Free-Body Force Diagram


  A diagram showing all the forces acting on an object. It is a good starting point to any mechanics problem
• Free-Fall


  An object is said to be in free fall when the only force acting on it is the force of gravity
• Gravitational Field Strength


  The force per unit mass exerted on a small test mass placed within the field
• Gravitational Potential Energy


  The component of an object’s energy due to its position in a gravitational field
• Kinetic Energy


  A form of energy that all moving objects possess. It is directly proportional to the mass of the object, and to the square of its velocity
• Moment of a Force

  The product of a force and the perpendicular distance from the line of action of the force to the pivot
• Momentum


  The product of an object’s mass and linear velocity
• Newton’s First Law of Motion

  An object will remain in its current state of motion, unless acted on by a resultant force. An object requires a resultant force to be able to accelerate
• Newton’s Second Law of Motion

  The sum of the forces acting on an object is equal to the rate of change of momentum of the object
• Newton’s Third Law of Motion

  Every action has an equal and opposite reaction. If an object exerts a force on another object, then the other object must exert a force back, that is opposite in direction and equal in magnitude
• Power


  The rate of transfer of energy
• Projectile Motion


  The motion of an object that is fired from a point and then upon which only gravity acts. When solving projectile motion problems, it is useful to split the motion into horizontal and vertical components
• Scalar Quantity


  A quantity that only has a magnitude, without an associated direction. Examples include speed, distance, and temperature
• Terminal Velocity

  The maximum velocity of an object that occurs when the resistive and driving forces acting on the object are equal to each other
• Uniformly Accelerated Motion

  Motion where the acceleration is constant. This allows the use of the SUVAT equations
• Vector Quantity


  A quantity that has both a magnitude and an associated direction. Examples include velocity, displacement, and acceleration
• Velocity-Time Graph

  Plots showing how velocity changes over a period of time. The gradient gives acceleration. The area beneath the graph gives change in displacement. Curved lines represent changing acceleration
• Weight


  The force of gravity on an object, the product of the object’s mass and the acceleration due to gravity
• Work Done

  The energy transferred by a force moving over a distance. It is equal to the product of the magnitudes of the force and dis
• Work Done

  The energy transferred by a force moving over a distance. It is equal to the product of the magnitudes of the force and distance
• Materials


  • Breaking Stress
  • Compression
  • Density
  • Elastic Deformation
  • Elastic Limit
  • Elastic Strain Energy
  • Force-Compression Graph
  • Force-Extension Graph
  • Hooke’s Law
  • Laminar Flow
  • Limit of Proportionality
  • Plastic Deformation
  • Stiffness
  • Strain
  • Stress
  • Stress-Strain Graph
  • Tensile Forces
  • Turbulent Flow
  • Upthrust
  • Viscosity
  • Viscous Drag
  • Yield Point
  • Young Modulus
• Breaking Stress


  The maximum stress a material can withstand without fracturing
• Compression


  The result of two coplanar forces acting into an object. Compression usually results in a reduction in the length of the object
• Density


  The mass per unit volume of a material
• Elastic Deformation


  If a material deforms with elastic behaviour, it will return to its original shape when the deforming forces are removed. The object will not be permanently deformed
• Elastic Limit


  The maximum stress that can be applied to an object without plastic deformation
• Elastic Strain Energy


  The energy stored in an object when it is stretched. It is equal to the work done to stretch the object and can be determined from the area under a force-extension graph
• Force-Compression Graph


  The gradient of a force-compression graph for a spring obeying Hooke’s law is equal to the spring constant. The area under the graph is the work done in stretching the spring
• Force-Extension Graph


  The gradient of a force-extension graph for a spring obeying Hooke’s law is equal to the spring constant. The area under the graph is the work done in stretching the spring
• Hooke’s Law

  The extension of an elastic object will be directly proportional to the force applied to it up to the object’s limit of proportionality
• Laminar Flow


  A state of flow where layers of fluid move together in parallel with little or no mixing between layers