Give an overview of the rotation of a rigid body around and axis
All points of the body perform circular motion
The circular trajectories lie in parallel planes
The centres of the axis lie on the axis of rotation
What is the equation for circular motion?
What are the equation for angular acceleration and velocity?
What are the equations for distance travelled,velocity and tangential acceleration?
What is centripetal force?
The force of constant magnitude pointing towards the centre of rotation
Needed for uniform rotation of a particle of mass (m)
Centripetal force= Fc- changes the direction of velocity and gives rise to the centripetal acceleration ac
What is the equation for centripetal force and acceleration?
Describe torque moment
How do you separate the components of heterogenous systems?
Place the Heterogeneous in the field of an appropriate force
What is sedimentation?
Separation of the components of heterogenous systems by gravity
What is the equation for Sedimentation?
In which situations can the heterogeneous system not be separated by sedimentation?
What are the drawbacks to sedimentation?
Gravitational forces are weak so it often takes place very slowly or is impossible because of diffusion
What is centrifugation?
Separation of the components of heterogeneous systems by the centripetal force
What is the equation for centrifugation?
In what situation can the heterogeneous system not be separated by centrifugation?
Give an overview of sedimentation rate and the duration of centrifugation
Give an overview of the sedimentation rate
What are the equations for the sedimentation coefficient and the relative centrifugal force?
Describe the centrifuge
▪️Instrument used for the separation of heterogeneous systems by rotation ▪️main parts -axis -rotor -motor(fixed angle or swinging bucket)
What are the key points regarding rotor balancing?
▪️The overall radial force on the rotor must be very small or centrifuge may be damaged ▪️Tubes must be loaded symmetrically in the rotor ▪️The masses of tubes must be equal
What are the different centrifugation methods?
▪️Differential centrifugation ▪️Gradient centrifugation -zone velocity centrifugation -isopycnic centrifugation
Describe differential centrifugation
Describe zone velocity centrifugation
describe isopycnic centrifugation