PREVIOUSLY ASKED IN:
WBPSC Miscellaneous Preliminary 2023
Answer
Centrifugation
Explanation
A washing machine's spin dryer works on the principle of centrifugation (or centrifugal force). When the drum spins at high speeds, an outward-directed force pushes the water particles away from the center and out through the small holes in the drum, effectively drying the clothes. A cream separator works on the exact same principle.
Key Points
- > Centrifugal force acts outward, away from the center of rotation.
- > Centripetal force acts inward, toward the center (keeps planets in orbit).
- > Centrifugal force is often described as a 'pseudo' or apparent force.
- > Cream separators in dairies use centrifugation.
- > Capillary action causes oil to rise in a lamp wick.
- > Osmosis allows plant roots to absorb water from the soil.
- > Medical centrifuges separate blood plasma using this principle.
Additional Information
Physics Principles in Daily Life
| Device/Phenomenon | Principle/Force |
|---|---|
| Spin Dryer | Centrifugation (Outward) |
| Planets Orbiting | Centripetal force (Inward) |
| Ink absorbing in chalk | Capillary action |
| Hydraulic lifts | Pascal's Law |
Memory Tips
- Fleeing the Center: Centrifugal has an 'f', like Fleeing the center. Water flees the clothes in a washing machine.