NATS 1720 Lecture Notes - Lecture 3: Rarefaction, Longitudinal Wave, Threshold Of Pain

• School: York University
• Department: Natural Science
• Course: NATS 1720
• Professor: Carl Wolfe

Document Summary

Two ways to look at/describe wave: time, position (space) Frequency=number of complete cycles per unit time (second) Transverse wave: motion of particles is perpendicular motion of wave longitudinal wave: motion of particles is in same direction as wave motion. Collisions with container walls exerts a force. Whenever a force acts o(cid:374) a(cid:374) o(cid:271)je(cid:272)t. it (cid:272)ha(cid:374)ges the o(cid:271)je(cid:272)t"s state of (cid:373)otio(cid:374) The net force on a wall, is the result of each collision (at an instant) adding up. Property of gas describing force exerted on walls of container. The basic unit of force is newton (n) (to life 1kg requires 10n) The basic unit of pressure newtons per square metre, 1n/m2=1 pascal (pa) In a fluid at contact density the pressure is same in all directions. Thin metal strip moves in response to pressure changes. Overpressure: change from normal at atmospheric pressure (can be positive or negative) Sound wave is alternating zones of + and over pressure.