initial commit / add all books

6 files changed, 63 insertions, 0 deletions

diff --git a/1535/CH18/EX18.1/Ch18Ex1.sci b/1535/CH18/EX18.1/Ch18Ex1.sci
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index 000000000..ca65d4c76
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+++ b/1535/CH18/EX18.1/Ch18Ex1.sci
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+// Scilab Code Ex18.1: Output power of the sound source : Page-361 (2010)

+r = 200;    // Distance of the point of reduction from the source, m

+I_0 = 1e-012;    // Final intensity of sound, watt per metre square

+I_f = 60;       // Intensity gain of sound at the point of reduction, dB

+// As A_I = 10*log10(I/I_0), solving for I

+I = I_0*10^(I_f/10);    // Initial Intensity of sound, watt per metre square

+P = 4*%pi*r^2*I;    // Output power of the sound source, watt

+printf("\nThe output power of the sound source = %3.1f W", P);

+

+// Result

+// The output power of the sound source = 0.5 W 
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diff --git a/1535/CH18/EX18.2/Ch18Ex2.sci b/1535/CH18/EX18.2/Ch18Ex2.sci
new file mode 100755
index 000000000..a5b5fc6dc
--- /dev/null
+++ b/1535/CH18/EX18.2/Ch18Ex2.sci
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+// Scilab Code Ex18.2: Change in sound level for doubling intensity: Page-361 (2010)

+I1 = 1;    // For simplicity assume first intensity level to be unity, W per metre square

+I2 = 2*I1;    // Intensity level after doubling, watt per metre square

+dA_I = 10*log10(I2/I1);    // Difference in gain level, dB

+printf("\nThe sound intensity level is increased by = %1d dB", dA_I);

+

+// Result

+// The sound intensity level is increased by = 3 dB 
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diff --git a/1535/CH18/EX18.3/Ch18Ex3.sci b/1535/CH18/EX18.3/Ch18Ex3.sci
new file mode 100755
index 000000000..d1804daa7
--- /dev/null
+++ b/1535/CH18/EX18.3/Ch18Ex3.sci
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+// Scilab Code Ex18.3: Total absorption of sound in the hall: Page-361 (2010)

+V = 8000;    // Volume of the hall, metre cube

+T = 1.5;    // Reverbration time of the hall, s

+alpha_s = 0.167*V/T;    // Sabine Formula giving total absorption of sound in the hall, OWU

+printf("\nThe total absorption of sound in the hall = %5.1f OWU", alpha_s);

+

+// Result

+// The total absorption in the hall = 890.7 OWU 
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diff --git a/1535/CH18/EX18.4/Ch18Ex4.sci b/1535/CH18/EX18.4/Ch18Ex4.sci
new file mode 100755
index 000000000..42c5bf8ce
--- /dev/null
+++ b/1535/CH18/EX18.4/Ch18Ex4.sci
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+// Scilab Code Ex18.4: Average absorption coefficient of the surfaces of the hall: Page-362 (2010)

+V = 25*20*8;      // Volume of the hall, metre cube

+S = 2*(25*20+25*8+20*8);    // Total surface area of the hall, metre square

+T = 4;    // Reverbration time of the hall, s

+alpha = 0.167*V/(T*S);    // Sabine Formule giving total absorption in the hall, OWU

+printf("\nThe total absorption in the hall = %5.3f OWU per metre square", alpha);

+

+// Result

+// The total absorption in the hall = 0.097 OWU per metre square
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diff --git a/1535/CH18/EX18.5/Ch18Ex5.sci b/1535/CH18/EX18.5/Ch18Ex5.sci
new file mode 100755
index 000000000..75e7cd899
--- /dev/null
+++ b/1535/CH18/EX18.5/Ch18Ex5.sci
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+// Scilab Code Ex18.5: Reverbration time for the hall : Page-362 (2010)

+V = 475;      // Volume of the hall, metre cube

+s = [200, 100, 100];    // Area of wall, floor and ceiling of the hall resp., metre square

+T = 4;    // Reverbration time of the hall, s

+alpha = [0.025, 0.02, 0.55];    // Absorption coefficients of the wall, ceiling and floor resp., OWU per metre square

+alpha_s = 0;

+for i=1:1:3

+    alpha_s = alpha_s + alpha(i)*s(i);

+end

+T = 0.167*V/alpha_s;    // Sabine Formula for reverbration time, s

+printf("\nThe reverbration time for the hall = %4.2f s", T);

+

+// Result

+// The reverbration time for the hall = 1.28 s 
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diff --git a/1535/CH18/EX18.6/Ch18Ex6.sci b/1535/CH18/EX18.6/Ch18Ex6.sci
new file mode 100755
index 000000000..70af6fcdd
--- /dev/null
+++ b/1535/CH18/EX18.6/Ch18Ex6.sci
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+// Scilab Code Ex18.6: Gain of resultant sound intensity: Page-362 (2010)

+I0 = 1;    // For simplicity assume initial sound intensity to be unity, watt per metre square

+A_I1 = 80;    // First intensity gain of sound, dB

+A_I2 = 70;    // Second intensity gain of sound, dB

+// As A_I = 10*log10(I/I_0), solving for I1 and I2

+I1 = 10^(A_I1/10)*I0;    // First intensity of sound, watt per metre square

+I2 = 10^(A_I2/10)*I0;    // Second intensity of sound, watt per metre square

+I = I1 + I2;    // Resultant intensity level of sound, watt per metre square

+A_I = 10*log10(I/I0);    // Intensity gain of resultant sound, dB

+printf("\nThe intensity gain of resultant sound = %6.3f dB", A_I);

+

+// Result

+// The intensity gain of resultant sound = 80.414 dB 
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