forces

• What is a scalar quantity?

  A quantity that only has a magnitude
• Why is a scalar quantity not direction dependent?

  Because it only has magnitude and no associated direction
• What is a vector quantity?

  A quantity that has both a magnitude and an associated direction
• How can a vector quantity be represented visually?

  • As an arrow
  • The length of the arrow represents the magnitude
  • The arrow points in the associated direction
• What is a force?

  A push or pull acting on an object due to an interaction with another object
• What are the two categories that all forces can be split into?

  1. Contact forces (objects touching)
  2. Non-contact forces (objects separated)
• Give three examples of contact forces.

  1. Friction
  2. Air resistance
  3. Tension
• Give three examples of non-contact forces.

  1. Gravitational forces
  2. Electrostatic forces
  3. Magnetic forces
• Is force a vector or a scalar quantity?

  Vector
• What does it mean for force to be a vector quantity?

  It has both a magnitude and an associated direction
• Give three examples of vector quantities.

  1. Velocity
  2. Displacement
  3. Force
• Give six examples of scalar quantities.

  1. Temperature
  2. Time
  3. Mass
  4. Speed
  5. Distance
  6. Energy
• What is weight?

  The force that acts on an object due to gravity and the object’s mass
• What quantities does weight depend on?

  Weight depends on the object's mass and the gravitational field strength
• What is the formula for weight?

  Weight = mass x gravitational field strength
• What is the unit used for weight?

  The Newton (N)
• What is the unit used for gravitational field strength?

  N/kg
• What is meant by an object’s centre of mass?

  The single point where an object’s weight can be considered to act through
• What piece of equipment can be used to measure an object’s weight?

  A calibrated spring-balance or newton-meter
• What is the name given to the single force that is equivalent to all the other forces acting on a given object?

  The resultant force