CHAPTER ONE: OSCILLATORY MOTION- PART THREE: DIRECT QUESTION AND ANSWERS

1) Define Oscillatory Motion? <strong>Ans: Oscillatory motion is defined as To and fro motion of an object from its mean position.</strong> 2) Define periodic motion? <strong>Ans: periodic motion is a motion of an object that regularly repeats or returns to a given position after fixed time interval.</strong> 3) What is period? <strong>Ans: Period is the time taken to make one complete cycle.</strong> 4) What is the SI unit of period? <strong>Ans: the SI unit of period is second (S)</strong> 5) What is frequency? <strong>Ans: Frequency is number of cycle made in one second.</strong> 6) What is the SI unit of frequency? <strong>Ans: the SI unit of frequency is Hertz (HZ).</strong> 7) List some examples of repetitive motion of Human body. <strong>Ans: Some examples of repetitive motion of Human body are:- a) Heart beat b) Breathing</strong> 8) Define simple harmonic motion. <strong>Ans1: Simple harmonic motion (SHM) is a type of motion under the influence of restoring force described by Hook’s law. Ans2: Simple harmonic motion SHM is a motion in which a body moves back or forth over a fixed path, returning to each position and velocity after definite interval of time.</strong> 9) What is the force constant or restoring force? <strong>Ans: force constant is the spring constant refers to the property of the material and shows the stiffness of the spring.</strong> 10) What is the displacement of Simple harmonic motion SHM? <strong>Ans: It the distance from equilibrium position in either direction.</strong> 11) State Hook’s law? <strong>Ans: Hook’s law states that the restoring force applied by a spring is proportional to the displacement of the spring and opposite in direction.</strong> 12) Define Amplitude. <strong>Ans: Amplitude is the maximum displacement from mean position in either direction.</strong> 13) What is simple pendulum? <strong>Ans: Simple pendulum is the mass on the end of the string which oscillates in a harmonic motion.</strong> 14) What is the period of simple pendulum depend on? <strong>Ans: The period of simple pendulum depend on • The length of the string. • Acceleration due to gravity.</strong> 15) What is equilibrium position? <strong>Ans: Equilibrium position is the rest position of particles.</strong> 16) A vibrating simple pendulum of a period is placed in a lift is accelerating downwards. What will be the effect on the time period? <strong>Ans: Time period increases as effect value of acceleration due to gravity decrease.</strong> 17) If you doubled the period of a pendulum, what happens to its length? <strong>Ans: Its length will be doubled</strong>