Forces

• What are the two types of quantities in physics?

  Scalar and vector quantities
• What unit is mass measured in?

  Kilograms (kg)
• What unit is temperature measured in?

  Degrees Celsius (°C)
• What unit is distance measured in?

  Metres (m)
• What unit is time measured in?

  Seconds (s)
• What unit is energy measured in?

  Joules (J)
• What do scalar quantities have?

  Size only
• What do vector quantities have?

  Magnitude and direction
• What is the unit for velocity?

  Metres per second (m/s)
• What is displacement measured in?

  Metres (m)
• What is the difference between scalar and vector quantities?

  Scalar quantities have size only, while vector quantities have both magnitude and direction
• How are vectors represented?

  Vectors are represented by arrows, where the length of the arrow represents the magnitude and the direction of the arrow represents the direction
• What are the two main types of forces?

  Contact forces and non-contact forces
• What is Newton's 3rd law?

  When two objects interact, the forces they exert on each other are equal in magnitude and opposite in direction
• What is the difference between mass and weight?

  Mass is the amount of matter in an object and remains constant, while weight is the force acting on an object due to gravity and varies with location
• How can you measure the weight of an object?

  Using a calibrated spring balance (Newton meter)
• What is the unit for gravitational field strength (g)?

  N/kg
• What are some applications of force?

  • Engineering
  • Space exploration
  • Artificial limbs
• What is the difference between speed and velocity?

  Speed is a scalar quantity, while velocity is a vector quantity
• What is a resultant force?

  A single force that Has the same effect as all individual forces acting together on an object
• What does a resultant force determine?

  Acceleration or deceleration of an object

  remain at rest (forces are balanced)
• What happens when forces are balanced?

  The object remains at rest or moves uniformly
• How do you calculate resultant forces when they act in the same direction?

  • Add the forces together
  • Resultant force is the sum of forces
• How do you calculate resultant forces when they act in opposite directions?

  • Subtract the smaller force from the larger force
  • Resultant force is the difference
• What does it mean if there is no resultant force?

  Forces are balanced and no acceleration occurs
• What is the resultant force when forces are balanced?

  Resultant force is zero
• What happens to an object when unbalanced forces act on it?

  The object accelerates or decelerates
• What is an isolated object or system?

  One where only internal forces are considered
• What is a free body diagram used for?

  • Shows all forces acting on an object
  • Arrows represent forces
  • Length indicates magnitude
  • Direction shows force direction
• What do arrows in a free body diagram represent?

  Forces acting on an object
• How is the length of an arrow in a free body diagram significant?

  It indicates the magnitude of a force
• What does the direction of an arrow in a free body diagram indicate?

  The direction of the force applied
• How can a single force be resolved into components?

  • Into perpendicular components (horizontal and vertical)
  • Components together have the same effect as the original force
• What do vector diagrams represent?

  • Use arrows to represent forces
  • Length indicates magnitude
  • Direction shows the force's direction
• How do you draw a vector diagram?

  1. Choose a suitable scale
  2. Draw the first force as an arrow
  3. From the tip of the first arrow, draw the next force at the correct angle
  4. Measure the resultant force from the start to the end of the last arrow
  5. Scale the resultant to the correct magnitude
• What is the formula for work done?

  Work = Force x Distance
• What happens to energy when work is done?

  Energy is transferred to or from an object
• How is 1 joule defined in terms of force and distance?

  1 joule = 1 newton-meter
• What occurs when no displacement happens despite applying force?

  No work is done if there is no displacement
• What is the relationship between work done, force applied, and distance moved?

  • Work done is directly proportional to:
  • Force applied
  • Distance moved in the direction of the force