Centrifugal force – meet the resistance

Research laboratories, the pharmaceutical and dairy industries, and the nuclear-energy sector around the world put this resistance to clever use in a machine called the centrifuge. 
| Photo Credit: K Ananthan/The Hindu

Ever felt a force pushing you outward, away from the centre, when you are riding a merry-go-round? It’s the centrifugal force. It is a force that an object perceives when it is moving in a curved path – always in the direction away from the centre of the path of rotation.

The centrifugal force is often called an actual force but it is really the product of inertia – the tendency for an object to maintain its state of motion. Unlike actual forces, which arise from an interaction between forces like gravity or magnetism, the centrifugal force arises when an object resists a change of direction. And moving on a curved path is to constantly change direction.

Research laboratories, the pharmaceutical and dairy industries, and the nuclear-energy sector around the world put this resistance to clever use in a machine called the centrifuge. Mixtures of substances are placed in small containers that are spun very fast. The centrifugal force pushes on each component of the mixture according to its density. So the less-dense components are separated from their denser counterparts.

But you can see the force at work in the humble washing machine itself, which dries clothes in the spin cycle by expelling water from them using the centrifugal force.