Churning and Magnetic Separation

Churning

Have you ever wondered how butter is made? It comes from milk or curd.

Definition: Churning is the process of shaking or rotating milk or curd vigorously to separate butter.

How it works

• Milk/Curd is a mixture where fat particles (butter) are suspended in the watery liquid (buttermilk).
• When churned using a mathni (traditional churner) or a machine:
  • The lighter component (butter) floats to the top.
  • The heavier liquid (buttermilk/chhach) remains below.

Magnetic Separation

This method utilizes the magnetic properties of certain metals.

Definition: Separation of magnetic and non-magnetic substances by using a magnet is called magnetic separation.

Key Concept: Magnetic vs Non-Magnetic

• Magnetic Substances: Iron, Nickel, Cobalt.
• Non-Magnetic Substances: Wood, Plastic, Sand, Glass.

Application

1. Carpentry: If a carpenter drops iron nails into sawdust, they can easily retrieve them by moving a magnet over the mixture. The nails stick to the magnet, leaving the sawdust behind.
2. Waste Management: In large junk yards, cranes fitted with powerful electromagnets move over heaps of garbage to separate scrap iron for recycling.