IB PHYSICS



IB PHYSICS GOHS

CHAPTER 13 TEST REVIEW: SHM and WAVES

Concepts

1. What is Simple Harmonic Motion? Give real world examples that are close to being SHM. Periodic motion that obeys Hooke’s Law.

2. Be able to define: amplitude, crest, frequency, height, longitudinal wave, mechanical wave, period, simple pendulum, transverse wave, trough, wavelength Check Chp 13 Crossword

3. Be able to speak to the amplitude, velocity, acceleration and restoring force of the object based due to position, as demonstrated by the picture to the right. How is this related to a simple pendulum? Amplitude = greatest +/- displacement; Velocity greatest at equilibrium; Acceleration greatest at Amplitude; Restoring force returns object to equilibrium only inertia keeps object going past equilibrium. Pendulum is same as spring system when angle is between 5o – 15o.

4. What is the difference in kinetic energy, gravitational potential energy and elastic potential energy? Give examples of each. KE measure energy of motion (a rolling ball); PEg measures energy associated with position (a falling ball); PEs measure energy associated with elasticity of a spring (a bouncing ball).

5. Draw a pendulum system. Show its equilibrium position. Show how the positive and negative amplitudes are related to other. Answer to the right:

6. What is the relationship between frequency and period in SHM? They are inversely related.

7. SHM is sinusoidal. Are transverse waves sinusoidal? Explain. How can longitudinal waves be represented as sinusoidal? Transverse are sinusoidal because particles of matter move perpendicular to the motion of the wave. Longitudinal can be viewed as sinusoidal when graphing compressions and rarefactions (density) over time.

8. What is the difference between constructive interference and destructive interference? In your explanation be sure to define phase. Constructive interference is to make a pulse bigger b/c the they are in phase; destructive is to make the phase smaller b/c they are out of phase. Phase is the displacement direction relative to equilibrium.

9. Discuss the reflection of a wave on a rope when one end is fixed. When one end is a free boundary. Fixed = reflection is opposite in phase; free boundary = reflection is same in phase.

10. What is the equation that represents conservation of energy when dealing with SHM? Answer: [pic]

Problems

1. A spring with constant k=475 N/m stretch 4.50 cm when an object is hung. What is the force on the spring? [pic] 21.4 N

2. A spring with constant k=475 N/m stretch 4.50 cm when an object of mass 25.0 kg is attached to the end of the spring. Find the acceleration of gravity in this location. [pic] 0.856 m/s2

3. A car starts at rest and rolls down a hill from a height of 10.0 m. It then moves across a level surface and collides with a light spring-loaded guardrail with 130,000 J of energy. Neglecting friction, what is the maximum distance the spring is compressed if the spring constant is 1.0 x 106 N/m? [pic] 0.13 m

4. A 0.500 kg object connected to a light spring with a spring-constant of 20.0 N/m oscillates on a frictionless horizontal surface with amplitude of 3.00 cm. What is the velocity of the object when the displacement is 2.00 cm? [pic] 0.141 m/s

5. A 1300 kg object is supported by a spring. The spring has a spring constant of 20,000 N/m. Find the period of the spring. Find also the frequency and the angular frequency. [pic] T = 1.6 s; f = 0.63 Hz; ω = 4.0 rad/s

6. If the object-spring system is described by x=(0.330m)cos (1.50t), find the amplitude, the angular frequency, the frequency, the period, and the position of when t=0.250 s. [pic] A = 0.330 m; ω = 1.50 rad/s; f = 0.239 Hz; T = 4.18 s; x = 0.307 m

7. Using a small pendulum of length 0.171 m, a geophysicist counts 72.0 complete swings in a time of 60.0 s. What is the value of g in this location? [pic] 9.79 m/s2

8. A wave traveling in the positive x-direction is pictured. Find the amplitude, wavelength, speed and period of the wave if it has a frequency of 8.00 Hz. [pic] A = 15 cm; λ = 40 cm; v = 3.20 m/s; T = 0.125 s

-----------------------

[pic]

................
................

In order to avoid copyright disputes, this page is only a partial summary.

Google Online Preview   Download