How does a vacuum cleaner pull in dust?
Show answer & explanation
Answer: Fan creates low pressure inside
Fan creates low pressure inside ✓ — Correct! Pressure differential! Fan (impeller) inside vacuum spins, pushing air out exhaust. Creates low pressure inside machine. Outside air (atmospheric pressure ~101 kPa) is higher pressure—flows into low pressure region. Air rushing into vacuum carries dust/debris with it. It's not 'sucking'—outside air PUSHING! Same reason airplane cabins need pressurization, straws work (lungs create low pressure), space suits needed (vacuum of space). Suction = pressure difference!
Static electricity pulls debris — Wrong. No electrostatic attraction (though some vacuums use static filters). Suction is air pressure difference—fan creates low pressure region.
Nozzle shape channels airflow — Wrong. Nozzle shape optimizes airflow, but basic suction mechanism is pressure difference created by fan pushing air out.
More Physics in Daily Life questions
- In a warm office that already reads 26 C, which change can make people feel cooler without lowering the thermostat?
- Why might 26 C feel acceptable in a breezy naturally ventilated summer building but too warm in a sealed winter office?
- On a warm humid day, why can the same 27 C room feel much worse once you start sweating?
- Why can moving air make a 27 C room feel cooler without changing the thermometer?
- Which hidden factor can make a desk beside a cold window feel chilly even when the thermostat across the room still reads 22 C?
- In the same 22 C room, why might someone who just climbed stairs feel warm while someone sitting in a T-shirt feels chilly?