Chapter 7 - Waves

Question 1

Calculate propagation speed (v) of a wave

Answer 1

V = f*lamda

Question 2

Period equation

Answer 2

T = 1/f

Question 3

Constructive interference

Answer 3

Waves that are in phase: displacement of resultant wave is sum of two interacting waves

Question 4

Destructive interference

Answer 4

Perfectly out of phase

Displacements counteract each other and the amplitude of the resultant wave is the difference between the two

***at 180º the resultant has zero amplitude

Question 5

What frequencies are audible to healthy young adults?

Answer 5

20 to 20,000 Hz

Question 6

What type of wave is sound?

Answer 6

Longitudinal

Question 7

What mediums can sound travel through?

Answer 7

Solid, liquid, gas…but not a vacuum

Question 8

Equation for speed of sound

Answer 8

V = √B/p

B = bulk modulus 
p = density of medium 

Sound travels fastest through solid

Question 9

What is speed of sound in air at 20ºC?

Answer 9

Around 343 m/s

Question 10

Pitch

Answer 10

Our perception of frequency

Question 11

Doppler effect

Answer 11

Difference between our perceived freq vs actual frequency

F’ = f (v+_ Vd)/ (v+_Vs)

Top = towards
Bottom = away

Question 12

Sound intensity

Answer 12

Average rate of energy transfer per area across a sur case that is perpendicular to the wave

SI unit is W/m^2

I = P/A

Question 13

Wave chapter was glanced over

Answer 13

If you have time read past Doppler effect