A node is a point along a standing wave where the wave has minimum amplitude.For instance, in a vibrating guitar string, the ends of the string are nodes. By changing the position of the end node through frets, the guitarist changes the effective length of the vibrating string and thereby the note played. Physics 8A Fall 2005 (Yury Kolomensky) PRACTICE PROBLEMS FOR THE FINAL Maximum score: 200 points 1. (25 points) Ice in a Glass You are riding in an elevator holding a glass of water with an ice cube floating in it. (a) (10 points) When the elevator is at rest, what fraction of the ice is submerged in water ?

A node is a point along a standing wave where the wave has minimum amplitude.For instance, in a vibrating guitar string, the ends of the string are nodes. By changing the position of the end node through frets, the guitarist changes the effective length of the vibrating string and thereby the note played.