- 93 Views
- Uploaded on

Download Presentation
## PowerPoint Slideshow about ' The Speed of Sound' - lucine

**An Image/Link below is provided (as is) to download presentation**

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript

Speed of Sound

- Much slower than the speed of light (values for air)
- Light – 300,000,000 m/s
- Sound – 332 m/s

Calculating Speed of Sound

- Assuming no pressure change from atmospheric,

V = 332 + 0.59T

- The speed of sound in air at 0C is 332m/s, the speed increases by 0.59m/s for every degree celsius raised

Practice Question

- What is the speed of sound in this room?

Changing the Medium

- Sound can travel through solid, liquid or gas
- Speed of sound depends on three things:
- Density of particles
- Closer particles are together – faster vibration can travel
- Gas – slow, solid – fast
- Sound travels faster on a humid day

- Faster the particles move, the quicker the vibration can be transferred
- Warm – Fast, Cold – slow
- Mass of the Particles
- Heavier the particles, the slower the vibration travels

Questions:

- Calculate the speed of sound if the temperature is: a) 1C b) 30C c) -10 C
- If the frequency of a radio wave is 102.1Mhz and the temperature of the air outside is 15C, what is the wavelength of the radio wave?
- A student is located 100m away from the school’s bell. If the bell rings, how long will it take the sound to reach the student’s ear if the temperature outside is -15 C?
- A swimmer is under the water while their friend is on the shore. If they are both the same distance away from a boat that is approaching, who will hear the boat first?
- Will sound travel faster at sea level or at the top of a mountain? The equator or the north pole? Explain.

Reflection of Sound

- Echoes – sound that reflects off a barrier and returns to the source
- Only use the following formula for echoes:

v = 2d/t

V – speed of sound

d – distance from source to reflective barrier

t – time for sound to return

- Uses sound to detect things underwater
- Process called echolocation – by analyzing echoes (reflected sound) we can detect objects

- Bats and dolphins use echolocation to find prey and locate things around themselves
- http://www.youtube.com/watch?v=gZxLUNHEmPw

Homework

- How long would an echo take to return from the Titanic if it is 4.0km below the surface of the Atlantic? The speed of sound in sea water is 1531m/s.
- A ship is sailing on a foggy night. The captain is worried about ice bergs but has no radar. The captain sounds the ships horm and hears the echo 2.4s later. If the air temperature is -10C, how far away is the ice berg.
- Research and explain how bats use echolocation to determine the location of their prey.

Download Presentation

Connecting to Server..