1. v = f λ 2. Use v = f. Find the wavelength of a sound wave created by a 440-Hz tuning fork in air that is at 25.0 o C. (First, find the speed at that temperature). v = 331.4 m/s + ( 0.6 ) T = 331.4 m/s + ( 0.6 )( 25 o C ) = 346.4 m/s f λ = v f = 346.4 m/s 440 Hz = λ = 0.78 m Sound Worksheet 1 Answers

2. 3. A certain sound wave has a wavelength of 3.0 m on a day that the temperature is 10 o C. Find the wavelength when the sound wave enters air of 25 o C. v = f λFrequency remains constant v = f λ λ f = v λ = 337.4 m/s 3.0 m = f = 112 Hz v 10 = 331.4 m/s + ( 0.6 ) T = 331.4 m/s + ( 0.6 )( 10 o C ) = 337.4 m/s

3. v 25 = 346.4 m/s v = f λ f λ = v f = 346.4 m/s 112 Hz λ = 3.08 m 3. A certain sound wave has a wavelength of 3.0 m on a day that the temperature is 10 o C. Find the wavelength when the sound wave enters air of 25 o C.

4. d = v t = ( 346.4 m/s )( 4.0 s ) 4. You are storm-watching on a 25 o C day. If lightning strikes and it takes 4.0 seconds for the sound to reach you, how far away was the bolt? How far is this in miles? v 25 = 346.4 m/s d = 1386 m = 1400 m d = 1386 m 1610 m 1 mi = 0.86 mi