Physics

1. Zero resultant force

   Nota:

   • A stationary object remains stationary if the sum of the forces acting upon it - resultant force - is zero. A moving object with a zero resultant force keeps moving at the same speed and in the same direction.
2. Resultant force of more than zero

   Nota:

   • If the resultant force acting on an object is not zero, a stationary object begins to accelerate in the same direction as the force. A moving object speeds up, slows down or changes direction.
3. a single force that has the same effect as all the forces acting on a object

Nota:

• Gravitational Potential Energy and Kinetic Energy

1. Assume all GPE change to KE
2. Ep=mxgxh

   Nota:

   • Ep=mxgxh Joules=kgxn/kgxmeters

1. To do with movement of an object
   1. Collisions and explosions
2. If something is not moving the momentum is zero
3. The conservation of momentum

1. Friction slows things down
2. Drag increases as speed increases
3. Terminal velocity
   1. Objects falling through fluids reach terminal velocity
   2. Steady speed
   3. In falling objects it depends on
      1. Shape
         1. Streamlined=will fall faster
      2. Area
         1. Small area=less air resistance

1. Electrons move
   1. Electrons move away-positive charge
2. Charges attract
3. Opposites repel

1. Symbols
2. A basic circuit is used to test components
3. Voltmeter
   1. Measures potential difference in volts
4. Ammeter
   1. Measures the current in amps
5. Potential Difference-Current Graphs

1. Plum Pudding
   1. Atoms are solid
2. Rutherford
   1. Firing beams of alpha particles at gold foil