Physics


1. Centrifugal Force


During a part of the drug production process at GSK, a centrifuge will be used to dry the product into powder form. This is to increase the shelf life of the product, as compared to when it is in liquid form. Cost savings can be achieved as less resources will need to be committed to the storage of the products.


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By applying physics concepts in industrial applications in GSK, we can understand how centrifugal force is an effective way in converting the product from liquid to powder form. By spining the content in the drum at high speed, the solid paticles are seperated from solvent, allowing the retrival of the product.

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Objects in a centrifuge is rotated at high speed by the jet turbine around a fixed axis, thus applying a force perpendicular to the axis. The sedimentation principle uses the centripetal acceleration to evenly separate substances of varying density.



*Fun Corner - Egg-beater as Centrifuge!

A hand-powered egg beater can act as a centrifuge for separating plasma from blood, thanks to modifications made by US scientists. Chemists at Harvard University and Cambridge have carried out the work to enable point-of-care disease detection in developing countries, where conventional equipments are too expensive or logistically-impossible to bring into.
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Related resources on egg-beater centrifuge:




2. Ideal Gas Law


The ideal gas law is the equation of state of a hypothetical ideal gas. It is a good approximation to the behavior of many gases under many conditions, although it has several limitations.

An ideal gas is defined as one in which:
  • All collisions between atoms or molecules are perfectly elastic
  • No intermolecular attractive forces (no interaction between molecules)
    *All internal energy is in the form of kinetic energy -> any change in internal energy is accompanied by a change in temperature

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The products produced in GSK have very low thermal tolerance, as they decompose under high temperature. Therefore, a vacuum dryer is deployed to facilitate the vapourisation of the organic compound. By decreasing the vapour pressure of the surroundings (as shown in the equation), the rate of vapourisation remains high, even at lower temperature. This allows the product to dry effectively, ensuring they are do not decompose.

The ideal gas law is illustrated in the video below.

By adjusting the pressure of the system, water could be made to boil at 40 degree Celsius!




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