Forces

?
  • Created by: Jo Wells
  • Created on: 27-12-12 14:01
View mindmap
  • Forces
    • Weight, Mass & Gravity
      • Weight = Mass X Gravitational Field Strength
        • W = m X g
      • Gravity = makes things ACCELERATE towards ground & gives everything WEIGHT
      • Weight (N) = a force
      • Mass (Kg) = NOT a force
      • Weight = caused by pull of gravitational force
      • Mass = amount of 'stuff' in an object
    • Resultant Force
      • = Overall force on something
        • e.g. a teapot = gravity acting downwards (10N), causing a reactant force acting upwards (10N) (keeping object stationary)
      • Decides MOTION of object
        • Whether it will ACCELERATE, DECELERATE or stay at a STEADY SPEED
      • Means a CHANGE in VELOCITY
        • e.g. moving car = driving force 1000N left, with air resistance 600N right = 400N (left)
    • & Acceleration
      • If resultant force on a stationary object = ZERO, object will STAY stationary
      • If there is NO resultant force on a moving object, it'll carry on at the SAME velocity (steady)
      • If there is a NON-ZERO resultant force, object will ACCELERATE in direction of force
        • starting, stopping, speeding up, slowing down & changing direction
        • Resultant force (N) = mass (Kg) X acceleration (m/s squared)
          • F = m X a
      • Reaction forces = EQUAL & OPPOSITE
    • Frictional force
      • Friction slows things down
        • Acts in opposite direction to movement
      • DRAG from fluids (air or liquid)
        • Reduce drag by STREAMLINING
        • Drag increases as speed increases
    • Terminal velocity
      • Objects falling through fluids reach a terminal velocity
        • At start, gravity = much more than frictional force, so they ACCELERATE
          • As speed increases, friction increases = gradually reduces acceleration until frictional force = accelerating force
            • = its maximum speed or TERMINAL VELOCITY
      • Terminal velocity of falling objects depends on SHAPE & AREA

Comments

No comments have yet been made

Similar Physics resources:

See all Physics resources »See all Forces and Motion resources »