Physics for IGCSE & O level - Waves And Sounds (Section 2 - No. 23)
Why is ultrasound used for cleaning delicate machinery?
It uses heat to melt away dirt.
It uses vibrations to dislodge dirt.
It uses high pressure to blast away debris.
It dissolves the dirt with chemicals.
Explanation
Ultrasound uses vibrations to dislodge dirt and grease.