Top-Rated Free Essay
Preview

Physics Unit 4 Notes

Satisfactory Essays
606 Words
Grammar
Grammar
Plagiarism
Plagiarism
Writing
Writing
Score
Score
Physics Unit 4 Notes
Unit 4 Physics Notes
Sunday, November 3, 2013

8:09 PM

Any Single disturbance is called a pulse
A series of pulses is called a wave

In the case of the impatient student, his disturbance was parallel to the direction of the wave itself. Also called a Longitudinal Wave

WAVES
• Waves can transmit two things
○ Can transmit energy
 Ex. Light waves from the sun heat the earth
○ Can transmit information
 Ex. Radio wave

When the motion of the particles is perpendicular to the motion of the wave, it is called a traverse wave
Pointing down
Acceleration down

Wave -> We see the motion of the medium
Soundwaves -> air
Lightwaves = electromagnetic waves
Stadium waves -> people
Water waves -> water
Light waves -> no medium
Pointing up
Acceleration up

Without tension, there can be no traverse waves in a medium.
-> Do not occur inside liquids and gases -> can occur on surface of water though

Inner core of earth has a liquid core, because traverse waves do not got through
Earthquakes can produce traverse, longitudinal, or a combination of the two.
-> longitudinal = compression, travel fast, primary (happen first)
-> traverse = "__________ waves", secondary (happen second)
-> longer delay between S and P waves, means greater distance from the epicenter

A)
B)
C)
D)

Crest
Trough
Amplitude
Wavelenght
Cycle -> one complete wavelength
Amplitude -> half the distance from crest and trough
Wavelength -> distance of one complete cycle (SI units = meters)
Period (T) -> time for one wavelength to pass (SI Units = seconds)
Frequency (f) -> number of cycles that pass by per time interval
= Cycles per second = 1 Hertz (Hz)
T=(1/f) and f=(1/T)
Ex. f=2 Hz = T=.5 seconds

Swing?

Applied force at a regular interval, causes you to go higher, high amplitude

All object will vibrate of oscillate at a certain frequency called the natural frequency
A pendulum (or swing) will swing back and forth at a natural frequency that depends only on it's lenght When a system is driven at it's natural frequency (forces applied in rhythm with the natural frequency),
Physics Unit 4 Page 1

The shorter the stick, the higher the
Natural frequency.

When a system is driven at it's natural frequency (forces applied in rhythm with the natural frequency), the oscillations will get bigger. This s termed resonance.

If two things have the same natural frequency,
And you hit one, the second will also begin to vibrate

Energy
Transfer

Unequal natural frequency, then vibrations won't transfer

It is possible for an object to have more than one natural (resonant) frequency. Natural frequency is the 1st harmonic
Other harmonics can be produced as well

If the displacement is one wavelength, then the time equals a period (T).
Wave Speed (or Velocity)
Wave Velocity

Velocity = Displacement/time = d/t

F = 1/T
T = 1/f

V = ʎ (wave length) / T (Period)
V = fʎ

Ex. Distance between waves is 6m, and one wave takes 4 seconds.
T=4
F = 1/4 Hz
V = (1/4) x 6m = 1.5 m/s

Ex.
1st

2nd

3rd

Aver.

Speed

10cm

1.3

1.5

1.5

1.4

5.7m/s

30cm

1.5

1.3

1.7

1.5

5.3m/s

50cm

Transverse

Amp

1.6

1.4

1.5

1.5

5.3m/s

Compression

Amplitude = amount of energy being transmitted Energy effects amplitude, not speed

ʎ

T1

T2

T3

Aver.

Speed

8

1.3

1.4

1.5

1.4

5.7m/s

14

.72

.74

.74

.73

5.4m/s

2.67

.40

.46

.50

.48

5.0m/s

What factors affect the speed of the wave?
Amplitude = no
Wave Length = no
Only the properties of the medium affect the wave speed

When waves meet, their amplitudes add (called the principle of superposition). After they meet, they pass through each other. Each wave in no way alters the travel of the other.

Physics Unit 4 Page 2

Amplitude of the wave has
NO EFFECT on the speed of it

Effect of different wave length on speed of wave
= NO EFFECT

You May Also Find These Documents Helpful

  • Powerful Essays

    1.a Up, up, and away [15] A balloonist can’t resist throwing a drink to another balloonist. The ‘thrower’ is moving at v = -15j m/min while the ‘catcher’ is moving at v = 15j m/min. At the instance the former throws the drink the ‘catcher’ is at (3i – 10j) m from the ‘thrower’. If the throw is horizontal, at what speed does the drink need to be thrown to be caught?…

    • 1252 Words
    • 6 Pages
    Powerful Essays
  • Satisfactory Essays

    Use your graph to estimate the time taken for the child to travel 15 metres.…

    • 414 Words
    • 2 Pages
    Satisfactory Essays
  • Powerful Essays

    Physics Gcse Unit 1 Aqa

    • 2231 Words
    • 9 Pages

    * Can travel through a vacuum, this is how we get energy from the sun…

    • 2231 Words
    • 9 Pages
    Powerful Essays
  • Good Essays

    Hsc Physics Notes - Space

    • 488 Words
    • 2 Pages

    9.2 - 1. The Earth has a gravitational field that exerts a force both on it and around it…

    • 488 Words
    • 2 Pages
    Good Essays
  • Good Essays

    marine science ch.3

    • 1781 Words
    • 7 Pages

    3. Scientists know that the outer core of the Earth is liquid because S waves have not survived travel through the Earth's interior.…

    • 1781 Words
    • 7 Pages
    Good Essays
  • Good Essays

    3. Where would it be most likely that you would find internal waves in the ocean?…

    • 1849 Words
    • 8 Pages
    Good Essays
  • Powerful Essays

    Physics Notes HSC

    • 32437 Words
    • 130 Pages

    Perform an investigation and gather information to determine a value for acceleration due to gravity using pendulum motion or computer assisted technology and identify reason for possible variations for the value of 9.8m/s2…

    • 32437 Words
    • 130 Pages
    Powerful Essays
  • Good Essays

    Year 10 physics summary

    • 1236 Words
    • 5 Pages

    Potential and chemical energy are all stores of energy because they are not actively doing anything but waiting to be changed into another type of energy.…

    • 1236 Words
    • 5 Pages
    Good Essays
  • Good Essays

    AQA Physics P1

    • 871 Words
    • 4 Pages

    P1
 AQA
 –
Revision
Notes
 1. Heat Transfer • Thermal radiation = infra-red radiation (beyond red part of visible spectrum)…

    • 871 Words
    • 4 Pages
    Good Essays
  • Satisfactory Essays

    Exam #2 Notes

    • 879 Words
    • 4 Pages

    What is public opinion? What is political socialization? Agents of Political Socialization. Does variables such as income, education, race, gender, and ethnicity, create differences in public opinion in America? If so, how so? Provide examples. What is ideology? What are some of the views of liberals and conservatives? What is a public opinion poll? A sample? Random digit dialing? What is a poll push? What is political efficacy? What three media sources are dominant in terms of how Americans get their news? Of the three, which one is more heavily regulated than the others and why? Which of the three has the least protection under the 1st Amendment? What is the FCC? According to your textbook, are publishers today concerned with informing people about the news, perpetuating a bias, or with business operations and profits? What does the right of rebuttal mean? Be able to discuss what is meant by nationalization of the news and consequences. What factors affect media coverage?What does agenda setting, framing, and priming mean? Provide examples.…

    • 879 Words
    • 4 Pages
    Satisfactory Essays
  • Satisfactory Essays

    My name is Ryan(student code 100556101), and i was wondering if i'm able to take either Physics 1010 or Physics 1030. I read online that you need high school calculus and vectors to take Physics 1010 otherwise you can take Physics 1030, Am i allowed to take either-or being a bridging student? or am i only allowed to take Physics 1030. If you need anymore information feel free to…

    • 70 Words
    • 1 Page
    Satisfactory Essays
  • Good Essays

    Year 10 Physics

    • 330 Words
    • 2 Pages

    5) State Newtons First Law. Explain the first law using the rockets as your examples.…

    • 330 Words
    • 2 Pages
    Good Essays
  • Powerful Essays

    In Mechanics and Physics, simple harmonic motion (SHM) is a periodic motion that is neither driven on damped by external forces. An object in simple harmonic motion experiences a net force which relates to Hooke’s law. Hooke’s law states “Force is directly proportional to the displacement from the equilibrium position and acts in the opposite direction of the displacement”.…

    • 1517 Words
    • 7 Pages
    Powerful Essays
  • Good Essays

    The Feminist Movement

    • 540 Words
    • 3 Pages

    Feminism is a struggle against sexist oppression. The feminist movement is how women’s rights and status in the world have changed over the years. Series of campaigns were done for issues such as, reproductive rights, equal pay, sexual violence, domestic violence and many more.…

    • 540 Words
    • 3 Pages
    Good Essays
  • Good Essays

    Ocean Waves

    • 381 Words
    • 2 Pages

    A wave is a periodic disturbance in space and time, possibly transferring energy to or through a space-time region. Have you ever ridden a wave in the ocean? Ocean waves travel on the surface of the water. You can see them and you can feel them. As you swim through the water, you can even make your own waves. The winds cause waves on the surface of the ocean (and on lakes). The wind transfers some of its energy to the water, through friction between the air molecules and the water molecules. Stronger winds (like storm surges) cause larger waves.…

    • 381 Words
    • 2 Pages
    Good Essays