PHY138 – Waves, Lecture 4 Today’s overview

Slides:

Advertisements

Similar presentations

The difference between sound and light They’re both waves, after all.

Advertisements

Waves Students will learn about waves. Waves Waves transfer energy without the transfer of mass. A wave is a vibratory disturbance that is transmitted.

PHY138 – Waves, Lecture 4 The Plan for Today: Sound and Light Medical Applications of Ultrasound Power and Intensity The Doppler Effect.

James T. Shipman Jerry D. Wilson Charles A. Higgins, Jr. Waves and Sound Chapter 6.

Chapter 14 Sound AP Physics B Lecture Notes.

PHYS16 – Lecture 35 Sound December 3, 2010 “Since light travels faster than sound, is that why some people appear bright until you hear them speak?”

Ultrasound Medical Imaging Imaging Science Fundamentals.

Chapter 1: Waves Review PowerPoint.

James T. Shipman Jerry D. Wilson Charles A. Higgins, Jr. Waves and Sound Chapter 6.

1.Sound must have a medium through which to travel. Through which medium – solid, liquid, or gas – does sound travel faster? 2.How are different musical.

Energy in Waves. A Wave is… Any disturbance that transmits energy through matter or space. Energy in Waves.

Chapter 15.2 – Characteristics of Waves amplitude – the maximum distance that the particles of a wave’s medium vibrate from their rest position -in a transverse.

Sonar: SOund NAvigation and Ranging Ships use reflected sound waves to locate objects underwater Echolocation: Bats use reflected sound waves to navigate.

PWV. Waves and Vibrations Benchmark 4 Describe different types of waves and their technological applications.

PHY II – Waves The Wave Model Speed of Waves on a String Sinusoidal Waves Spherical Waves, Plane Waves.

Mechanical Waves and Sound

Waves Introduction Chapter 10 Section 1 and 2 Physics Standard 4.

Chapter 15 4 Wave Motion. Section 15-1: Simple Wave Motion Transverse and Longitudinal Waves A transverse wave.

Principles of Earth and Physical Science Mr. Taylor Rainier Jr/Sr High School.

Physics 101: Lecture 33 Sound

Waves Chapter Wave motion A wave is the motion of a disturbance.

17.4 Sound and Hearing You can identify sounds without seeing them because sound waves carry information to your ears. People who work in places where.

Sound and Light Chapter 12. Sound A longitudinal wave that spreads in all directions Speed depends on medium –Solids and liquids = quick movement –Gasses.

PHY138 – Waves, Lecture 3 “..imagine a stadium full of people doing "the wave" with a giant sheet covering them so that none of the spectators can be seen.

Waves & Wave Properties Introduction to Wave Properties

Waves Unit 4 Ch 8 MHR. Introduction A wave is a disturbance that transfers energy through a medium. A medium is a material through which a wave travels.

PHY138 – Waves, Lecture 3 Today’s overview The Wave Model Speed of Waves on a String Sinusoidal Waves Spherical Waves, Plane Waves.

What is sound? Sound is a longitudinal wave which travels through the air through a series of compressions and rarefactions.

PHY138 – Waves, Lecture 2 “Physics is like sex: sure, it may give some practical results, but that’s not why we do it.” - Richard Feynman, Nobel Laureate.

Reading Assignment Next week’s reading is Knight Chapter 23, Sections 23.1 – There is a pre-class quiz on for this material.

Senior Science Information Systems

Waves Friday, January 8, 2010.

Sound and Light Chapter 12.

PHY138 – Waves, Lecture 3 Today’s overview

Mechanical Waves and Sound

Electromagnetic spectrum

Electromagnetic Radiation

Sound, Light, Electromagnetic Spectrum and Mirrors

Analyze functions of two variables

Wave Parts WAVES.

Week 5 Light waves.

WAVES 8th Grade Science.

Comparing Energy.

Mechanical Waves and Sound

Physical Science: Optics

Sound Vs. Light.

PHY138 – Waves, Lecture 1 Today’s overview

PHY138 – Waves, Lecture 5 Today’s overview

GCSE Knowledge Organiser Unit 1 – Waves

15.9 WAVES - Review.

Waves The water is vibrating up and down.

Office Hours: Mon. 6 PM, Wed. 2 PM, Wed. 6 PM, Fri. 9 AM

How fast does sound travel through a solid, liquid and gas?

Waves & Wave Properties Introduction to Wave Properties

The Nature of Sound Physics Chapter 16A.

PHY138 – Waves, Lecture 1 New instructor for November and December

How fast does sound travel through a solid, liquid and gas?

Light Light is a form of energy Energy has the ability to do work

Electromagnetic Radiation

4th 9 Weeks Review Key.

Review of waves.

Chapter 4-1 Sound.

Properties of Waves Part 2.

1 2 3 Waves A wave transfers energy

Mechanical Waves and Sound

PHY138 – Waves, Lecture 4 Today’s overview

About the Mechanics Test

Presentation transcript:

PHY138 – Waves, Lecture 4 Today’s overview Sound and Light Power and Intensity The Doppler Effect Medical Applications of Ultrasound

Reading Assignment Next week’s reading is Knight Chapter 21, Sections 21.1 – 21.8. There is a pre-class quiz on www.masteringphysics.com for this material due on Monday morning. A www.masteringphysics.com Problem Set on Chapter 20 is due on Friday at 5:00PM.

Sound and Light Sound is a pressure wave in a gas, liquid or solid. Speed depends on material. Light is one type of electromagnetic wave. In a vacuum, all electromagnetic waves (including light) travel at c = 3×108 m/s. In transparent media, light slows down. Index of Refraction is n > 1. This reduces the wavelength, but does not change the frequency!

Reflection of Transverse Wave Pulse (Chapter 21 concept.) A pulse traveling to the right on a heavy string attached to a lighter string Speed suddenly increases

Reflection of Transverse Wave Pulse A pulse traveling to the right on a light string attached to a heavier string Speed suddenly decreases

Physics of Ultrasound Speed of sound in bone, flesh and blood are all different When the speed of any wave suddenly changes, there is a reflection and transmission Ultrasound images are formed from reflected high frequency sound Image resolution is set by wavelength, λ λ=v/f, so higher frequency yields smaller λ, and better resolution

Speed of sound in humans Tissue Sound Speed (m/s) Air 350 Fat 1450 Brain 1540 Blood 1570 Bone 4080 Muscle 1585

Power and Intensity The Power, P, of any wave source is how much energy per second is radiated as waves [units = Watts] The Intensity, I, is the energy rate per area. This determines how loud (sound) or bright (light) the wave is. I=P/a, where a is an area perpendicular to the wave direction. At a distance r from a small source, the intensity is I=P/(4πr2)

Doppler Effect