chapter 13: oscillations about equilibrium whenever f = -kx or u(x) is a parabola u = kx 2 /2 f =...

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Chapter 13: Oscillations About Equilibrium Whenever F = -kx or U(x) is a parabola U = kx 2 /2 F = -kx

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Page 1: Chapter 13: Oscillations About Equilibrium Whenever F = -kx or U(x) is a parabola U = kx 2 /2 F = -kx

Chapter 13: Oscillations About Equilibrium

Whenever F = -kx or U(x) is a parabola

U = kx2/2

F = -kx

Page 2: Chapter 13: Oscillations About Equilibrium Whenever F = -kx or U(x) is a parabola U = kx 2 /2 F = -kx

Ch13-1 Periodic Motion

T = period – the time for one cycle or repeat time

f = frequency – the number of cycles per second

f = 1/T

= angular frequency – radians per second

= 2f = 2/T

Don’t confuse angular frequency with angular velocity.

Chapter 13: Oscillations About Equilibrium

Page 3: Chapter 13: Oscillations About Equilibrium Whenever F = -kx or U(x) is a parabola U = kx 2 /2 F = -kx

Ch13-2 Simple Harmonic Motion (SHM)

Chapter 13: Oscillations About Equilibrium

Page 4: Chapter 13: Oscillations About Equilibrium Whenever F = -kx or U(x) is a parabola U = kx 2 /2 F = -kx

Ch13-2 Simple Harmonic Motion (SHM)

Chapter 13: Oscillations About Equilibrium

Displaying Position Versus Time for Simple Harmonic Motion

t = 0x = Acos(2t/T)

Page 5: Chapter 13: Oscillations About Equilibrium Whenever F = -kx or U(x) is a parabola U = kx 2 /2 F = -kx

Ch13-2 Simple Harmonic Motion (SHM)

Chapter 13: Oscillations About Equilibrium

Simple Harmonic Motion as a Sine or a Cosine

Page 6: Chapter 13: Oscillations About Equilibrium Whenever F = -kx or U(x) is a parabola U = kx 2 /2 F = -kx

Ch13-2 Simple Harmonic Motion (SHM)

P13.8 (p.425)

Chapter 13: Oscillations About Equilibrium

Page 7: Chapter 13: Oscillations About Equilibrium Whenever F = -kx or U(x) is a parabola U = kx 2 /2 F = -kx

CT1: A mass attached to a spring oscillates back and forth as indicated in the position vs. time plot below. At point P, the mass has

A. positive velocity and positive acceleration.

B. positive velocity and negative acceleration.

C. positive velocity and zero acceleration.

D. negative velocity and positive acceleration.

E. negative velocity and negative acceleration.

F. negative velocity and zero acceleration.

G. zero velocity but is accelerating (positively or negatively).

H. zero velocity and zero acceleration.

Page 8: Chapter 13: Oscillations About Equilibrium Whenever F = -kx or U(x) is a parabola U = kx 2 /2 F = -kx

CT2: A mass suspended from a spring is oscillating up and down as indicated. Consider two possibilities: (i) at some point during the oscillation the mass has zero velocity but is accelerating (positively or negatively); (ii) at some point during the oscillation the mass has zero velocity and zero acceleration.

A. Both occur sometime during the oscillation.B. Neither occurs during the oscillation.C. Only (i) occurs.D. Only (ii) occurs.

Page 9: Chapter 13: Oscillations About Equilibrium Whenever F = -kx or U(x) is a parabola U = kx 2 /2 F = -kx

Ch13-3 Connections Between Uniform Circular Motion and SHM

Chapter 13: Oscillations About Equilibrium

Page 10: Chapter 13: Oscillations About Equilibrium Whenever F = -kx or U(x) is a parabola U = kx 2 /2 F = -kx

Ch13-3 Connections Between Uniform Circular Motion and SHM

Chapter 13: Oscillations About Equilibrium

Position Versus Time in Simple Harmonic Motion

Page 11: Chapter 13: Oscillations About Equilibrium Whenever F = -kx or U(x) is a parabola U = kx 2 /2 F = -kx

Ch13-3 Connections Between Uniform Circular Motion and SHM

Chapter 13: Oscillations About Equilibrium

Velocity Versus Time in Simple Harmonic Motion

Page 12: Chapter 13: Oscillations About Equilibrium Whenever F = -kx or U(x) is a parabola U = kx 2 /2 F = -kx

Ch13-3 Connections Between Uniform Circular Motion and SHM

Chapter 13: Oscillations About Equilibrium

Acceleration Versus Time in Simple Harmonic Motion

Page 13: Chapter 13: Oscillations About Equilibrium Whenever F = -kx or U(x) is a parabola U = kx 2 /2 F = -kx

Ch13-3 Connections Between Uniform Circular Motion and SHM

P13.22 (p.425)

Chapter 13: Oscillations About Equilibrium

Page 14: Chapter 13: Oscillations About Equilibrium Whenever F = -kx or U(x) is a parabola U = kx 2 /2 F = -kx

P13.66 (p.428)

Page 15: Chapter 13: Oscillations About Equilibrium Whenever F = -kx or U(x) is a parabola U = kx 2 /2 F = -kx

Ch13-4 The Period of a Mass on a Spring

P13.63 (p.427)

Chapter 13: Oscillations About Equilibrium

Page 16: Chapter 13: Oscillations About Equilibrium Whenever F = -kx or U(x) is a parabola U = kx 2 /2 F = -kx

P13.31 (p.426)

k

m1

Page 17: Chapter 13: Oscillations About Equilibrium Whenever F = -kx or U(x) is a parabola U = kx 2 /2 F = -kx

Factors Affecting the Motion of a Mass on a Spring

Page 18: Chapter 13: Oscillations About Equilibrium Whenever F = -kx or U(x) is a parabola U = kx 2 /2 F = -kx

Ch13-5 Energy Conservation in Oscillatory Motion

E = mv2/2 + kx2/2 = kA2/2 = mvmax2/2 = mA22/2

Chapter 13: Oscillations About Equilibrium

Page 19: Chapter 13: Oscillations About Equilibrium Whenever F = -kx or U(x) is a parabola U = kx 2 /2 F = -kx

Ch13-5 Energy Conservation in Oscillatory Motion

U = kA2cos2t/2 K = mA22sin2t/2 = kA2sin2t/2

Chapter 13: Oscillations About Equilibrium

Page 20: Chapter 13: Oscillations About Equilibrium Whenever F = -kx or U(x) is a parabola U = kx 2 /2 F = -kx

Ch13-5 Energy Conservation in Oscillatory Motion

P13.67 (p.428)

Chapter 13: Oscillations About Equilibrium

Page 21: Chapter 13: Oscillations About Equilibrium Whenever F = -kx or U(x) is a parabola U = kx 2 /2 F = -kx

CT3: In P13.67b, which principle do we have to use to get the speed of the bob and bullet right after the collision?

A. Newton’s laws.

B. Conservation of energy.

C. Conservation of momentum.

D. The work-kinetic energy theorem.

Page 22: Chapter 13: Oscillations About Equilibrium Whenever F = -kx or U(x) is a parabola U = kx 2 /2 F = -kx

CT4: In P12.67b, which principle do we have to use to get the speed of the bullet from the height the bob rises?

A. Newton’s laws.

B. Conservation of energy.

C. Conservation of momentum.

D. The work-kinetic energy theorem.

Page 23: Chapter 13: Oscillations About Equilibrium Whenever F = -kx or U(x) is a parabola U = kx 2 /2 F = -kx

Ch13-6 Simple Pendulum

Chapter 13: Oscillations About Equilibrium

Page 24: Chapter 13: Oscillations About Equilibrium Whenever F = -kx or U(x) is a parabola U = kx 2 /2 F = -kx

rt

Page 25: Chapter 13: Oscillations About Equilibrium Whenever F = -kx or U(x) is a parabola U = kx 2 /2 F = -kx

Ch13-6 Simple Pendulum

P13.67c (p.428)

Chapter 13: Oscillations About Equilibrium

Page 26: Chapter 13: Oscillations About Equilibrium Whenever F = -kx or U(x) is a parabola U = kx 2 /2 F = -kx

CT5: In P13.52a the acceleration of gravity at the surface of the Moon is one-sixth that at the surface of the Earth. If the pendulum were taken to the Moon, the period will

A. increase.

B. decrease.

C. stay the same.

Page 27: Chapter 13: Oscillations About Equilibrium Whenever F = -kx or U(x) is a parabola U = kx 2 /2 F = -kx

Simple Pendulum: Energy View

Page 28: Chapter 13: Oscillations About Equilibrium Whenever F = -kx or U(x) is a parabola U = kx 2 /2 F = -kx

Ch13-7 Damped Oscillations

Chapter 13: Oscillations About Equilibrium

Page 29: Chapter 13: Oscillations About Equilibrium Whenever F = -kx or U(x) is a parabola U = kx 2 /2 F = -kx

Ch13-7 Damped Oscillations

Chapter 13: Oscillations About Equilibrium

Page 30: Chapter 13: Oscillations About Equilibrium Whenever F = -kx or U(x) is a parabola U = kx 2 /2 F = -kx

Ch13-8 Driven Oscillations and Resonance

Chapter 13: Oscillations About Equilibrium