Forces and Motion

• What is the definition of speed?

  distance travelled per unit time
• What is the definition of velocity?

  speed in a given direction
• What is the definition of acceleration?

  chang in velocity per unit time
• How do you find velocity on a distance time graph?

  gradient
• What does a horizontal line mean on a distance time graph?

  stationary
• What does a curved line mean on a distance time graph?

  change in velocity and acceleration
• How do you calculate acceleration in a velocity time graph?

  gradient
• What does a horizontal line mean on a velocity time graph?

  constant speed
• How do you calculate distance on a velocity time graph?

  area under line
• A vector has a magnitude and direction
• A scalar has a magnitude
• What is the equivalent vector for the scalar distance?

  displacement
• What is the equivalent vector for the scalar speed?

  velocity
• Is time scalar or vector?

  scalar
• Is energy scalar or vector?

  scalar
• Is acceleration scalar or vector?

  vector
• Is force scalar or vector?

  vector
• How do you calculate speed on a distance time graph?

  gradient
• What is displacement?

  the difference in distance of start and end
• How can you tell something is decelerating on a distance time graph?

  gradient gets shallower
• How can you tell something is accelerating on a distance time graph?

  gradient gets steeper
• How do you find distance on a velocity time graph?

  area underneath
• What does a horizontal line mean on a velocity time graph?

  constant speed
• What is force?

  a push or pull
• What can force do to an object?

  slow it down, speed up, change direction, change shape
• What is air resistance?

  the force trying to precent movement between two surfaces
• What is upthrust?

  the force acting in a fluid
• Air resistance/friction goes in the opposite direction to movement
• Upthrust goes in the opposite direction to weight
• What is the equation for newton's second law of motion?

  f = ma
• What is the opposite force called?

  norma reaction force
• What is resultant force?

  one force replacing all other forces on an object hacing the same effect on motion of object
• What does it mean if resultant force is 0?

  stationary of constant speed
• What are the resultant forces of these?

  
• Normal reaction arrow and weight arrow must be same length as balanced
• What is elasticity?

  when a force is applied the object stores elastic energy and if elastic it will go back to original length when removed
• WHat is hooke's law?

  force is directly proportional to extension provided the elastic limit is not exceded
• How do we know from a graph that something obeys Hooke's Law?

  a straight line will pass through origin
• How do you calculate acceleration in terminal velocity?


  a = f/m
• Why does the skydiver slow when the parachute opens?

  increase in surface area so more air resistance