AS P1 Topics

AS P1 Topics

1. Buoyancy

   • Buoyancy occurs due to density of solid < density of liquid
     • Upthrust = Weight + Drag
       • 4/3 π r^3 ρ (fluid) = M(sphere) g + 6π η r v
   • Sinking occurs due to density of solid > density of liquid
     • M(sphere) g = 4/3 π r^3 ρ (fluid) + 6π η r v
       • Weight = Upthrust + Drag
   • Density = Mass of material for given volume: Kg/m^3
     • Mass = Density x Volume
     • Volume = Mass / Density
   • For terminal velocity, F=ma = 0
     • Can determine the viscosity using this!
   • Stoke's law (viscous drag) = 6π η r v
   • Boats

2. Resolution of vectors

   • Trigonometry
     • Sin(theta) = Opposite/Hypotenuse
     • Cos(theta) = Adjacent/Hypotenuse
     • Tan(theta) = Opposite/Adjacent
   • Pythagoras
     • C^2 = A^2 + B^2
   • Vectors can be resolved to horizontal and vertical forces

3. Materials

   • Hooke's law
     • F = -k x
   • Young modulus
     • Elastic region: The linear part of a stress-strain graph. If a material is deformed in this area it will go back to its original dimensions
     • Plastic region: The area where non-linear behaviour is seen on stress-strain graph. If this occurs then the material will remain deformed
   • Brittle: Very small region of plastic deformation before mechanical failure
   • Ductile: Can be drawn into wires
   • Malleable: Can be beaten into sheets and deformed

4. Friction

   • Resolution of vectors

5. Projectile Motion