Flashcards in Sound and Doppler Effect Deck (25):

1

## What is the speed of sound through air?

### 340 m/s

2

## Compare the velocity of sound in solids, liquids, gases.

### Vsolid > v liquid > v gas

3

## Explain how sound works

### Sound waves arise from longitudinal collisions between molecules around it. The more likely the molecules collide, then the more likely sound will be produced.

4

## Relate molecular weight and speed of molecules

### The heavier the molecule, then the slower it will travel.

5

## Relate intermolecular forces and speed of molecules

### The greater the intermolecular forces, then it will move faster to it's normal position.

6

## What range can humans process sound?

### 20 to 20,000 Hz.

7

## Relate pitch and frequency

###
The higher the pitch, the higher the frequency.

The lower the pitch, the lower the frequency.

8

## What is intensity?

### Intensity is related to how loud the sound is. Intensity is related the the amplitude of the wave. Large amplitude means, high intensity, and more loud.

9

## Equation for Intensity

### Power / Area. Watts/ meters squared.

10

## What is the intensity reference

### 10^-12 to 1 w/m^2

11

## What is the shortcut for decibels

### dB+10= 10(I)

12

## What is the formula for the doppler effect?

### FL = FS ( V+/-VL) / (V+/- VS)

13

## Relate frequency and relative motion.

###
Frequency increases as the objects get close.

Frequency decreases as the objects go away.

14

## Contrast nodes and antinodes

###
Nodes don't move

Antimodes have movement.

15

## What is the equation for frequency and wavelength for standing waves?

###
Frequency is: nv/ 2L

Wavelength is: 2L / n

velocity just depends on the type of string.

16

## How do you calculate the fundamental frequency ?

### Subtract two consecutive harmonics.

17

## How do you calculate beat frequency?

### Subtract two beats. Take the absolute value.

18

## What is the equation for frequency and wavelength for open pipes?

###
L = wavelength/ 2

frequency = v/ 2L

19

## What is the equation for frequency and wavelength for closed pipe?

### Frequency = nv/ 4L

20

## Most important equation for waves

### velocity = frequency (wavelength)

21

## Describe speed of gases in different types of temperatures.

### Speed of gases travels faster in warmer conditions.

22

## Relate wavelength, frequency, and changing mediums

### When sound goes from one medium to another, the frequency stays the same however the velocity and the wavelength change.

23

## Relate velocity and sound wave frequency when traveling through a medium.

### The velocity in a give medium is always the same regardless of the frequency.

24

## What is the formula for intensity of a sound wave?

### Intensity is power / area. Area is 4 PI r^4

25