Physics Help.....Please DO NOT ROUND the answer and Please show steps 1: A sound
ID: 1296562 • Letter: P
Question
Physics Help.....Please DO NOT ROUND the answer and Please show steps
1: A sound source emits sounds of frequency 180 Hz that travel through still air at 340 m/s. The listener moves at 85 m/s relative to still air toward the stationary source. What is the wavelength of the sound between the source and the listener?
Ans ; _________ m
My answer was this and it was wrong : 1.511 m
2: A door bell generates a 50 dB sound at a close distance. What is the intensity of the sound generated by the bell at the same distance?
Ans : ________ W/m2
My Answer was this and it was worng : 10^-6 W/m2
3:
The pressure and volume of a gas are changed along a path ABCA in the figure. The vertical divisions on the graph represent 1.00
Explanation / Answer
wavelength of the sound = 340 / 180
wavelength = 1.89 m
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dB = 10 * log ( I / 1.0 x 10-12 W/m2)
50 = 10 * log( I / 1.0 x 10-12 W/m2)
1.0 * 10-12 * 10(5.0) = I
I = 1 * 10-7 W/m2
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For segment AB, the process is isochoric W = 0J
For segment AB, the process is isobaric
w = P( Vf - Vi) = 1.00