Physics Triple Science

• What is a vector

  a vector is something that has both direction and magnitude
• What is a scalar ?

  A scalar is a physical quantity that had a magnitude but no direction
• examples of vectors?

  Force, velocity, acceleration, displacement
• examples of scalar?


  speed ,distance ,weight ,time
• How is average speed worked out?

  Average speed is calculated by dividing the total distance traveled by the total time taken.
• What does instantaneous mean?

  the speed at a particular point in the journey
• What does a horizontal line on a graph mean?

  it means the object is staionary
• what does a straight sloping line in a graph mean?

  means the object is travelling at a constant speed

  
• what does it mean if there is a straight sloping line going down in a graph?

  the object is returning to its start position
• The steeper the line..

  the faster an object is at travelling
• what can speed be calculated by?


  the gradient
• gradient=


  vertical difference between two points on a graph

  ---------------------------------------------

  horizontal difference between the same two points
• what does acceleration mean?

  Rate of change of velocity.
• what do we measure acceleration in?

  m/s^2 (meters per second squared)
• how do we work out velocity?

  final velocity - initial velocity

  ------------------------

  time
• a cheetah accelerates from rest to 30m/s in 3 secs. Calculate the acceleration.

  10m/s
• what is newtons first law?

  a object will not change its motion unless acted on by an unbalanced force
• if its at rest it will..

  stay at rest
• if it is in motion

  it will remain at the same velocity
• what does it mean if a object has a greater mass?

  More inertia and it takes more force to change their motion
• Give an example of newtons first law

  car at a stop light
• what does a horizontal line mean on a velocity time graph?

  it means the object is at a constant velocity
• what does a sloping line mean on a velocity time graph

  it shows that the object is accelerating
• how do you calculate the distance travelled by a object on a time velocity graph

  it can be calculated by the area under the velocity time graph
• What is weight ?

  how strongly gravity pulls on the matter
• what is gravity?

  an attraction force between objects with mass
• how do u work out gravity?

  weight= mass x gravity
• What is newtons second law?

  the acceleration of an object in the direction of the resultant force depends on

  the size of the force

  the mass of the object
• how do we work out force?

  force = mass x acceleration
• what does inertial mass do?

  it measures how difficult it is to change the velocity of an object
• what is newtons third law?

  for every action there is a equal or opposite reaction
• action-


  reaction forces are different to balanced forces because they are acting upon different objects
• what is a thinking distance?


  the distance travelled un between realising they need to brake and not actually braking
• what is braking distance?

  the distance taken to stop once the brakes are applied
• how do we work out stopping distance?

  thinking distance + braking distance
• what factors effect stopping distance?

  speed travelling

  mass of car

  worn brakes

  drugs - depressant[slow reaction time] - stimulant[fast reaction time]

  weather- slippery road