Forces and motion!

Forces and motion!

1. Speed, velocity &acceleration

   • speed
     • average speed =distance moved/time taken
       • on most journeys, the speed of a car varies, so the acctual speed is usually different- than the average speed
         • it is a SCALAR quantity
           • measured in m/s
   • velocity
     • velocity means the speed fof something AND its direction of travel
       • it is a VECTOR quantity
         • measured in m/s
   • acceleration
     • something is accelerating if its velocity is changing
       • average acceleration = change in velocity/ time taken
         • a = v-u / t
           • u= initial velocity, v= final velocity
           • measured in m/s^2

2. Free Fall

   • The acceleration of free fall, g
     • Acceleration of free fall is the same for ALL objectrs falling nearthe earth's surface.
       • The acceleration of free fall is represented by the symbol g , its value varies slightly from one place to another beausethe earths gravitational pull varies the simple figure used for equations is 10m/s^2
   • up and down