Question

Explain the working of centrifugal instrument in detail with respect to physics

Answer 1

A centrifuge is simply a machine that spins around to make a large and useful force. Small centrifuges are used in scientific laboratories (for example, to separate blood products). You can find much bigger ones in aerospace-labs, where they're used for testing astronauts, pilots, and their equipment to absolute breaking point.


Hold something heavy in one hand and whirl your arm around your head. Feel a force that seems to be pulling your shoulder out of its socket? That's the principle of the centrifuge at work—and you can look at it from two different angles. In popular books and magazines, people talk about something called centrifugal force: the force that seems to make things shoot outward when they go round in a circle.

Hold something heavy in one hand and whirl your arm around your head. Feel a force that seems to be pulling your shoulder out of its socket? That's the principle of the centrifuge at work—and you can look at it from two different angles. In popular books and magazines, people talk about something called centrifugal force: the force that seems to make things shoot outward when they go round in a circle.

if something is moving in a circle, there must be a force acting on it somewhere to make it turn, otherwise it would go in a straight line. So look at the situation carefully and figure out where the inward pushing or pulling force is coming from. That's the centripetal force. If some part of the object is flying outward, that's not because there's centrifugal force: it's because there's no centripetal force to make it go in a circle.



What is centrifugation ?

Centrifugation is a technique used for the separation of particles from a solution according to their size, shape, density, viscosity of the medium and rotor speed.

The particles are suspended in a liquid medium and placed in a centrifuge tube. The tube is then placed in a rotor and spun at a define speed.

Separation through sedimentation could be done naturally with the earth gravity, nevertheless, it would take ages. Centrifugation is making that natural process much faster.

Rotation of the rotor about a central axis generates a centrifugal force upon the particles in the suspension.

Which factors have an influence on centrifugation :

Density of both samples and solution

Temperature/viscosity

Distance of particles
displacement

Rotation speed

A centrifuge is a device that separates particles from a solution through use of a rotor. In biology, the particles are usually cells, subcellular organelles, or large molecules, all of which are referred to here as particles.

There are two types of centrifuge procedures; one is preparative, the purpose of which is to isolate specific particles, and the other is analytical, which involves measuring physical properties of the sedimenting particles.

As a rotor spins in a centrifuge, a centrifugal force is applied to each particle in the sample; the particle will then sediment at the rate that is proportional to the centrifugal force applied to it. The viscosity of the sample solution and the physical properties of the particles also affect the sedimentation rate of each particle.

At a fixed centrifugal force and liquid viscosity, the sedimentation rate of a particle is proportional to its size (molecular weight) and to the difference between the particle density and the density of the solution.