Final answer:
A centrifuge may shake excessively due to an imbalance of loads, mechanical issues, or operating at excessive speeds. The device uses centripetal acceleration and inertia to separate specimens by density.
Step-by-step explanation:
Excessive shaking in a centrifuge can be caused by several factors. One common reason is an imbalance in the loads inside the centrifuge. When samples are not evenly distributed or if there is a discrepancy in the weight of the test tubes, it can cause uneven forces during spinning, leading to excessive shaking. Another potential cause could be mechanical issues such as loose or worn out parts. Last but not least, operating a centrifuge at speeds higher than its recommended capacity could also lead to instability and shaking.
Centrifuges operate on the principle of centripetal acceleration, which is essential for the separation of specimens of different densities. Inertia plays a key role in this process, causing denser particles to sediment out while lighter ones remain in the fluid. With a large angular velocity, centrifuges are capable of achieving centripetal acceleration hundreds of thousands of times greater than Earth's gravity, greatly reducing the time required for sedimentation of various materials such as blood cells, viruses, and macromolecules.