Edexcel IGCSE Physics: 1 - Forces and Motion

    Cards (21)

    • What is a scalar quantity?
      A scalar quantity is a physical quantity that has magnitude but no direction (e.g. distance, time),
    • What is a vector quantity?
      A quantity that has both magnitude and direction (e.g. force, velocity).
    • Which property of a distance/time graph can be used to calculate speed?
      The gradient.
    • State the equation that links distance, time and speed.
      speed (m/s) = distance (m)/time (s)
      v = d/t
    • What is acceleration?
      Acceleration is the change in velocity per the unit of time.
      Measured in m/s^2.
    • State the equation that links acceleration, time and change in velocity.
      acceleration (m/s^2)= change in velocity (m/s)/time (s)
      a = (v-u)/t
    • Which property of the velocity/time graph can be used to calculate acceleration?
      The gradient.
    • Which property of a velocity/time graph can be used to calculate distance?
      The area under the graph.
    • State the equation linking final speed, initial speed, acceleration and distance travelled.
      final speed^2 (m/s) = initial speed^2 (m/s) + (2 * acceleration (m/s^2) * distance travelled (m))
      v^2 = u^2 +2as
    • Name two types of forces that always oppose motion.
      Friction and air resistance (drag)
    • What force holds planets around the sun?
      Gravitational force.
    • What force holds electrons around the nucleus?
      Electrostatic force.
    • In what way can a force affect the object that it is being applied on?
      It can change the shape of the object, e.g. extension or compression.
      It can change the direction that the object is moving in.
      It can change the speed of the object.
    • State the equation that links unbalanced force, mass and acceleration.
      force (N)= mass (kg) * acceleration (m/s^2)
      F = m * a
    • State the equation that links mass, weight and gravitational acceleration.
      weight (N) = mass (kg) * g (m/s^2)
      w = mg
    • What is the relationship between stopping distance, breaking distance and thinking distance of a car while stopping?
      stopping distance = thinking distance + braking distance
    • What are 3 factors that affect the stopping distance of a car?
      Reaction time, weather conditions and initial speed.
    • State 2 factors that affect the air resistance acting on a falling object.
      Surface area and speed
    • How does an object reach terminal velocity?
      At first the object falls under the effect of its weight accelerating with gravitational acceleration. As it accelerates, air resistance opposing the motion increases therefore resultant force acting on the object decreases and since f = ma, acceleration decreases.
    • What is Hooke's Law?
      Extension is directly proportional with the force applied.
    • What is the difference between elastic and plastic behaviour?
      In elastic behaviour, the object recovers its original shape when the forces causing the extension is removed.
      In plastic behaviour, there is a permanent deformation to the shape of the object when the forces are removed.