Question

The working principle of a washing machine is:

• A. Diffusion
• B. Centrifugation
• C. Reverse osmosis
• D. Dialysis

Hint:

Think about what happens physically when the drum spins very fast during the spin-dry cycle.

Answer 1

The Correct Option is B

Step 1: Recall the spin cycle.
During the spin cycle, the drum of a washing machine rotates at high speed with clothes and water inside it.
Step 2: Apply rotational physics.
Fast rotation pushes the contents of the drum outward, this outward-pushing effect during rotation is called centrifugation, the same principle used in a laboratory centrifuge.
Step 3: Explain water removal.
The water is flung outward through small holes in the drum wall and drains away, while the clothes, being too large to pass through the holes, remain inside and become much less wet.
Step 4: Rule out other options.
Diffusion is a slow spreading of particles from high to low concentration, unrelated to spinning. Reverse osmosis is a membrane-based water purification method. Dialysis is a medical technique for filtering blood, neither applies here.
Final Answer: B) Centrifugation.