SIMPLE HARMONIC MOTION WARM UP CHALLENGE USE A

SIMPLE HARMONIC MOTION

WARM UP (CHALLENGE! USE A slingshot consists of a light leather cup, containing a stone, that is YOUR NOTES!) pulled back against 2 rubber bands. It takes a force of 30 N to stretch the bands 1. 0 cm (a) What is the potential energy stored in the bands when a 50. 0 g stone is placed in the cup and pulled back 0. 20 m from the equilibrium position? (b) With what speed does it leave the slingshot? 3000 60 J 49 m/s N/m

PERIODIC MOTION Motion that repeats in a regular cycle Mass on a spring Vibrating guitar string Tree swaying in the wind Equilibrium Position- where the net force on the object is zero All other positions, there is a force working to bring the object back to equilibrium

PERIODIC MOTION Period (T) – amount of time needed for an object to complete one cycle of motion Frequency (f) – number of cycles in one second Amplitude – the maximum distance the object is from the equilibrium point

MASS ON A SPRING

MASS ON A SPRING AND ENERGY Where is there maximum potential energy? Where is there maximum kinetic energy? Max Potential: top and bottom of range of motion Max Kinetic: at equilibrium position

ENERGY DISTRIBUTION THROUGH RANGE OF MOTION (PAGE 384 OF YOUR TEXTBOOK!)

PENDULUMS A “bob” suspended by a string Where is max and min KE? Where is max and min PE?

PENDULUM DISPLACEMENTWhat is the amplitude? TIME GRAPH What is the period? (How long for one cycle? ) What is the frequency? (How many cycles in one second? )

PENDULUM DISPLACEMENTWhat is the amplitude? 0. 1 m TIME GRAPH What is the period? (How long for one cycle? ) 2 seconds/cycle What is the frequency? (How many cycles in one second? ) 0. 5 cycles/second