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Help with some questions

  1. Nov 9, 2006 #1
    I got a long exam review sheet and got all the answers except a few. If someone would help me out it would be greatly appreciated.

    1) Pendulum A has period 2 seconds. Pendulum B is four times as long as pendulum A. What is the period of pendulum B?

    A) 1 second

    B) 2 seconds

    C) 4 seconds

    D) 8 seconds

    2) What is the frequency of a vibration with period 0.02 second?

    A) 0.02 Hertz

    B) 0.02 second

    C) 50 Hertz

    D) 50 seconds

    3) Two tones which are one octave apart differ in frequency by a factor of

    A) 4

    B) 2

    C) 3/2

    D) 21/2

    9) How are standing waves and travelling waves different?

    A) Standing waves have no motion.

    B) Travelling waves have troughs become crests and vice versa.

    C) A travelling wave has a wave velocity.

    D) A standing wave is bigger.

    10) What is not true for a pendulum?

    A) Period depends on length

    B) Period depends on gravity

    C) Period depends on mass

    D) It is an anharmonic oscillator.

    11) The strings of a guitar vibrate at different frequencies. They have different thicknesses because

    A) a thinner string has more tension than a thicker string and vibrates more quickly.

    B) a thicker string has more tension than a thinner string and vibrates more quickly.

    C) a thicker, more massive string vibrates more slowly than a thinner string of the same length and tension.

    D) a thinner, less massive string vibrates more slowly than a thicker string of the same length and tension.

    Which of the following is not a harmonic oscillator?

    A) A tuning fork with its two tines vibrating rhythmically in opposite directions

    B) A superball bouncing on a ceramic tile floor

    C) A person bouncing gently up and down at the end of a bungee cord, near the end of the ride

    D) A vertical flagpole swaying back and forth

    The tides are strongest near the equator because that is where the

    A) centripetal force of the earth is strongest.

    B) earth’s gravity is weakest.

    C) centrifugal force due to the earth’s rotation is strongest.

    D) tidal bulges caused by the moon are tallest.

    35) Microwaves have wavelengths between

    1) 1 micron to 100 microns.

    2) 1 millimeter to 1 meter.

    3) 1 micrometer to 1 millimeter.

    4) 1 meter to 1000 meters.

    36) The speed of light is roughly 300,000,000 m/s. A radio station has frequency 100 megahertz. What is the station’s wavelength?

    1) 30,000,000,000 meters

    2) 3,000,000 meters

    3) 3.0 meters

    4) 0.33 meters

    39) If an electric field wave oscillates north and south, and the wave is travelling straight up, then what direction does the magnetic field wave oscillate?

    1) East and west

    2) North and south

    3) Up and down

    4) It does not oscillate: this situation is impossible.

    46) When a beam of charged particles that is flowing through space enters a stationary magnetic field, the beam’s speed

    1) decreases.

    2) increases.

    3) does not change.

    4) increases or decreases, depending on the direction of the magnetic field.

    If you know the answers to any of these it would be greatly appreciated.
  2. jcsd
  3. Nov 9, 2006 #2


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    Homework Helper

    We do not just do problems for people here. If you want to post your answers and your reasons for choosing them someone will be happy to help you with these. It would probbly be best to divide the post up into several smaller sets of related problems.
  4. Nov 9, 2006 #3
    Thanks for your help.
  5. Nov 9, 2006 #4


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