Wave and Optics Chapter #1 | Lecture Note

University:
California State University, Northridge
Course:
PHYS 100A | General Physics I
Academic year:

2024
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0

Pages:

45
Author:

customer-8144378

Osilation- the to and fro motion of a body about its mean position is Called osilation A vibratory motion And the body which osillate is called osilator. FOR EXAMPLE: Motion of Simple Pendulum Motion of Swing If You displace the pendulum from Equilibrium Position (mean Position) toward one side then force Pushed it back toward Equilibrium mean position this force is called Restoring force Some terminologies (i) Vibration To and fro motion of a body about its mean position is Called Vibration. if a body move from "O" and then come back to "O" after traveling distance of O->A->B->O then this is Called one vibration. (ii) Mean Position The point where body is at initial at rest is Called mean Position. -> At mean Position initially v=0, a=0, -> and when body is in motion The v=vmax at mean position -> The Restoring force also change direction at mean position Potential Energy is zero at mean position (iii) Time period Time required to Complete one vibration is Called Time period it is measured in "sec" (iv) Frequency Number of vibration in one second is Called frequency. its unit is Hertz v) Relation b/w T & F Time period & Frequency are reciprocal to one another Mathematically T = 1/f f = 1/T vi) Periodic Motion The motion which repeat it self in equal interval of time is Called Periodic Motion. eg * Swinging Pendulum * motion of moon around earth * Rotation of earth around its axis; etc vii) Displacement The Distance travel by a body from its mean position is Called Displacement viii) Amplitude The maximum Distance of the body from its mean position is Called Amplitude. * These are also known as turning points of motion * At Amplitude Velocity become zero * At Amplitude PE become maximum. (ix) Angular frequency Number of revolution in one Second is Called A. frequency Mathematically f = ω/2π SHIM (i) The type of osilatory motion in which acceleration is directly proportional to displacement Covered by a body and acceleration is always directed toward center mean position. (ii) The osilatory motion in which force is always directly proportional to Displacement & always directed toward mean position. P.T.O