Forces and Motion

Speed
1. Speed=Distance/Time
Force and movement
1. Can make objects do 5 things:
  1. Speed up
  2. Slow down
  3. Change direction
  4. Turn
  5. Change shape
Air resistance and Friction
1. Friction
  1. Bad points of it
    1. Always wastes energy
    2. Always limits the top speed
2. Air Resistance
  1. pushes against objects which are moving through the air
  2. slows objects down
    1. cars are STREAMLINED
Force and Rotation
1. Pivot
  1. point of rotation - like the middle of a see-saw. It is also known as a FULCRUM
2. Lever
  1. its a simple machine. Called a machine because ithelps us do work more easily
  2. RULE: The LONGER the lever, the GREATER the TURNING POINT about the pivot
  3. everyday examples: Scissors, wheelbarrows and doors
Moments
1. Moment = force x perpendicular distance
2. balancing moments
  1. anticlockwise moments = clockwise moments
Pressure
1. Pressure is how much FORCE is put on a certain AREA
2. measured in pascals (Pa).
  1. 1 Newton/metre2 = 1 Pascal
3. For a given force - a BIG AREA means a SMALL PRESSURE
  1. pressure is SMALL because the AREA is LARGE. this means that the force is SPREAD OUT over a BIGGER AREA so the pressure is LOW
4. For a given force - a SMALL AREA means a BIG PRESSURE
  1. pressure is large because the area is small. This means that the force is CONCENTRATED onto a SMALL AREA an NOT spread out so the pressure is HIGH

Resource summary

	Created by Jhil Kaushik over 3 years ago