initial commit / add all books

23 files changed, 592 insertions, 0 deletions

diff --git a/213/CH13/EX13.1/13_1.sce b/213/CH13/EX13.1/13_1.sce
new file mode 100755
index 000000000..6bb2f9b56
--- /dev/null
+++ b/213/CH13/EX13.1/13_1.sce
@@ -0,0 +1,10 @@
+//To find speed of gear F

+clc

+//Given:

+NA=975 //rpm

+TA=20, TB=50, TC=25, TD=75, TE=26, TF=65

+//Solution:

+//Calculating the speed of gear F

+NF=NA*(TA*TC*TE)/(TB*TD*TF) //rpm

+//Results:

+printf("\n\n Speed of gear F, NF = %d rpm.\n\n",NF)
\ No newline at end of file
diff --git a/213/CH13/EX13.10/13_10.sce b/213/CH13/EX13.10/13_10.sce
new file mode 100755
index 000000000..f01c34420
--- /dev/null
+++ b/213/CH13/EX13.10/13_10.sce
@@ -0,0 +1,22 @@
+//To find angular velocities

+clc

+//Given:

+TC=50, TD=20, TE=35

+NA=110 //rpm

+//Solution:

+//Calculating the number of teeth on internal gear G

+TG=TC+TD+TE

+//Speed of shaft B:

+//Calculating the values of x and y

+//From the fourth row of Table 13.9, y-x*(TC/TD)*(TE/TG) = 0        .....(i)

+//Also, x+y = 110, or y+x = 110                                     .....(ii)

+A=[1 -(TC/TD)*(TE/TG); 1 1]

+B=[0; 110]

+V=A \ B

+x=V(2)

+y=V(1)

+//Calculating the speed of shaft B

+NB=round(+y) //Speed of shaft B, rpm

+//Results:

+printf("\n\n Number of teeth on internal gear G, TG = %d.\n\n",TG)

+printf(" Speed of shaft B = %d rpm, anticlockwise.\n\n",NB)
\ No newline at end of file
diff --git a/213/CH13/EX13.11/13_11.sce b/213/CH13/EX13.11/13_11.sce
new file mode 100755
index 000000000..fb266fb58
--- /dev/null
+++ b/213/CH13/EX13.11/13_11.sce
@@ -0,0 +1,29 @@
+//To find angular velocities

+clc

+//Given:

+TA=12, TB=30, TC=14

+NA=1, ND=5 //rps

+//Solution:

+//Number of teeth on wheels D and E:

+//Calculating the number of teeth on wheel E

+TE=TA+2*TB

+//Calculating the number of teeth on wheel E

+TD=TE-(TB-TC)

+//Magnitude and direction of angular velocities of arm OP and wheel E:

+//Calculating the values of x and y

+//From the fourth row of Table 13.10, -x-y = -1, or x+y = 1            .....(i)

+//Also, x*(TA/TB)*(TC/TD)-y = 5                                        .....(ii)

+A=[1 1; (TA/TB)*(TC/TD) -1]

+B=[1; 5]

+V=A \ B

+x=V(1)

+y=V(2)

+//Calculating the angular velocity of arm OP

+omegaOP=-y*2*%pi //Angular velocity of arm OP, rad/s

+//Calculating the angular velocity of wheel E

+omegaE=(x*TA/TE-y)*2*%pi //Angular velocity of wheel E, rad/s

+//Results:

+printf("\n\n Number of teeth on wheel E, TE = %d.\n\n",TE)

+printf(" Number of teeth on wheel D, TD = %d.\n\n",TD)

+printf(" Angular velocity of arm OP = %.3f rad/s, counter clockwise.\n\n",omegaOP)

+printf(" Angular velocity of wheel E = %.2f rad/s, counter clockwise.\n\n",omegaE)
\ No newline at end of file
diff --git a/213/CH13/EX13.12/13_12.sce b/213/CH13/EX13.12/13_12.sce
new file mode 100755
index 000000000..3ec839da8
--- /dev/null
+++ b/213/CH13/EX13.12/13_12.sce
@@ -0,0 +1,15 @@
+//To find speed of shaft

+clc

+//Given:

+TB=80, TC=82, TD=28

+NA=500 //rpm

+//Solution:

+//Calculating the number of teeth on wheel E

+TE=TB+TD-TC

+//Calculating the values of x and y

+y=800

+x=-y*(TE/TB)*(TC/TD)

+//Calculating the speed of shaft F

+NF=x+y //Speed of shaft F, rpm

+//Results:

+printf("\n\n Speed of shaft F = %d rpm, anticlockwise.\n\n",NF)
\ No newline at end of file
diff --git a/213/CH13/EX13.14/13_14.sce b/213/CH13/EX13.14/13_14.sce
new file mode 100755
index 000000000..af75d66aa
--- /dev/null
+++ b/213/CH13/EX13.14/13_14.sce
@@ -0,0 +1,27 @@
+//To find number of teeth and speed

+clc

+//Given:

+NA=300 //rpm

+TD=40, TE=30, TF=50, TG=80, TH=40, TK=20, TL=30

+//Solution:

+//Refer Fig. 13.18 and Table 13.13

+//Calculating the speed of wheel E

+NE=NA*(TD/TE) //rpm

+//Calculating the number of teeth on wheel C

+TC=TH+TK+TL

+//Speed and direction of rotation of shaft B:

+//Calculating the values of x and y

+//We have, -x-y = -400, or x+y = 400                    .....(i)

+//Also, x*(TH/TK)*(TL/TC)-y = 0                         .....(ii)

+A=[1 1; (TH/TK)*(TL/TC) -1]

+B=[400; 0]

+V=A \ B

+x=V(1)

+y=V(2)

+//Calculating the speed of wheel F

+NF=-y //rpm

+//Calculating the speed of shaft B

+NB=-NF*(TF/TG) //Speed of shaft B, rpm

+//Results:

+printf("\n\n Number of teeth on wheel C, TC = %d.\n\n",TC)

+printf(" Speed of shaft B = %d rpm, anticlockwise.\n\n",NB)
\ No newline at end of file
diff --git a/213/CH13/EX13.15/13_15.sce b/213/CH13/EX13.15/13_15.sce
new file mode 100755
index 000000000..31a76df2f
--- /dev/null
+++ b/213/CH13/EX13.15/13_15.sce
@@ -0,0 +1,36 @@
+//To find velocity ratio

+clc

+//Given:

+T1=80, T8=160, T4=100, T3=120, T6=20, T7=66

+//Solution:

+//Refer Fig. 13.19 and Table 13.14

+//Calculating the number of teeth on wheel 2

+T2=(T3-T1)/2

+//Calculating the values of x and y

+//Assuming that wheel 1 makes 1 rps anticlockwise, x+y = 1            .....(i)

+//Also, y-x*(T1/T3) = 0, or x*(T1/T3)-y = 0                           .....(ii)

+A=[1 1; 1 T1/T3]

+B=[1; 0]

+V=A \ B

+x=V(1)

+y=V(2)

+//Calculating the speed of casing C

+NC=y //Speed of casing C, rps

+//Calculating the speed of wheel 2

+N2=y-x*(T1/T2) //Speed of wheel 2, rps

+//Calculating the number of teeth on wheel 5

+T5=(T4-T6)/2

+//Calculating the values of x1 and y1

+y1=-2

+x1=(y1-0.4)*(T4/T6)

+//Calculating the speed of wheel 6

+N6=x1+y1 //Speed of wheel 6, rps

+//Calculating the values of x2 and y2

+y2=0.4

+x2=-(14+y2)*(T7/T8)

+//Calculating the speed of wheel 8

+N8=x2+y2 //Speed of wheel 8, rps

+//Calculating the velocity ratio of the output shaft B to the input shaft A

+vr=N8/1 //Velocity ratio

+//Results:

+printf("\n\n Velocity ratio of the output shaft B to the input shaft A = %.2f.\n\n",vr)
\ No newline at end of file
diff --git a/213/CH13/EX13.16/13_16.sce b/213/CH13/EX13.16/13_16.sce
new file mode 100755
index 000000000..ea27b8148
--- /dev/null
+++ b/213/CH13/EX13.16/13_16.sce
@@ -0,0 +1,15 @@
+//To find speed of shaft

+clc

+//Given:

+TA=40, TB=30, TC=50

+NX=100, NA=NX //rpm

+Narm=100 //Speed of arm, rpm

+//Solution:

+//Refer Fig. 13.22 and Table 13.18

+//Calculating the values of x and y

+y=+100

+x=-100-y

+//Calculating the speed of the driven shaft

+NY=y-x*(TA/TB) //rpm

+//Results:

+printf("\n\n Speed of the driven shaft, NY = %.1f rpm, anticlockwise.\n\n",NY)
\ No newline at end of file
diff --git a/213/CH13/EX13.17/13_17.sce b/213/CH13/EX13.17/13_17.sce
new file mode 100755
index 000000000..8ff336537
--- /dev/null
+++ b/213/CH13/EX13.17/13_17.sce
@@ -0,0 +1,32 @@
+//To find speed of output shaft

+clc

+//Given:

+TB=20, TC=80, TD=80, TE=30, TF=32

+NB=1000 //rpm

+//Solution:

+//Refer Fig. 13.23 and Table 13.19

+//Speed of the output shaft when gear C is fixed:

+//Calculating the values of x and y

+//From the fourth row of the table, y-x*(TB/TC) = 0                .....(i)

+//Also, x+y = +1000, or y+x = 1000                                 .....(ii)

+A=[1 -TB/TC; 1 1]

+B=[0; 1000]

+V=A \ B

+x=V(2)

+y=V(1)

+//Calculating the speed of output shaft

+NF1=y-x*(TB/TD)*(TE/TF) //Speed of the output shaft when gear C is fixed, rpm

+//Speed of the output shaft when gear C is rotated at 10 rpm counter clockwise:

+//Calculating the values of x and y

+//From the fourth row of te table, y-x*(TB/TC) = +10                .....(iii)

+//Also, x+y = +1000, or y+x = 1000                                 .....(iv)

+A=[1 -TB/TC; 1 1]

+B=[10; 1000]

+V=A \ B

+x=V(2)

+y=V(1)

+//Calculating the speed of output shaft

+NF2=y-x*(TB/TD)*(TE/TF) //Speed of the output shaft when gear C is rotated at 10 rpm counter clockwise, rpm

+//Results:

+printf("\n\n Speed of the output shaft when gear C is fixed = %.1f rpm, counter clockwise.\n\n",NF1)

+printf(" Speed of the output shaft when gear C is rotated at 10 rpm counter clockwise = %.1f rpm, counter clockwise.\n\n",NF2)
\ No newline at end of file
diff --git a/213/CH13/EX13.18/13_18.sce b/213/CH13/EX13.18/13_18.sce
new file mode 100755
index 000000000..8dded6a25
--- /dev/null
+++ b/213/CH13/EX13.18/13_18.sce
@@ -0,0 +1,16 @@
+//To find speed of road wheel

+clc

+//Given:

+TA=10, TB=60

+NA=1000, NQ=210, ND=NQ //rpm

+//Solution:

+//Refer Fig. 13.24 and Table 13.20

+//Calculating the speed of crown gear B

+NB=NA*(TA/TB) //rpm

+//Calculating the values of x and y

+y=200

+x=y-210

+//Calculating the speed of road wheel attached to axle P

+NC=x+y //Speed of road wheel attached to axle P, rpm

+//Results:

+printf("\n\n Speed of road wheel attached to axle P = %d rpm.\n\n",NC)
\ No newline at end of file
diff --git a/213/CH13/EX13.19/13_19.sce b/213/CH13/EX13.19/13_19.sce
new file mode 100755
index 000000000..9bf0a2781
--- /dev/null
+++ b/213/CH13/EX13.19/13_19.sce
@@ -0,0 +1,26 @@
+//To find torque exerted

+clc

+//Given:

+TA=15, TB=20, TC=15

+NA=1000 //rpm

+Tm=100 //Torque developed by motor, N-m

+//Solution:

+//Refer Fig. 13.26 and Table 13.21

+//Calculating the number of teeth on gears E and D

+TE=TA+2*TB

+TD=TE-(TB-TC)

+//Speed of the machine shaft:

+//From the fourth row of the table, x+y = 1000, or y+x = 1000        .....(i)

+//Also, y-x*(TA/TE) = 0                                              .....(ii)

+A=[1 1; 1 -TA/TE]

+B=[1000; 0]

+V=A \ B

+y=V(1)

+x=V(2)

+//Calculating the speed of machine shaft

+ND=y-x*(TA/TB)*(TC/TD) //rpm

+//Calculating the torque exerted on the machine shaft

+Ts=Tm*NA/ND //Torque exerted on the machine shaft, N-m

+//Results:

+printf("\n\n Speed of machine shaft, ND = %.2f rpm, anticlockwise.\n\n",ND)

+printf(" Torque exerted on the machine shaft = %d N-m.\n\n",Ts)
\ No newline at end of file
diff --git a/213/CH13/EX13.2/13_2.sce b/213/CH13/EX13.2/13_2.sce
new file mode 100755
index 000000000..9ccc357d4
--- /dev/null
+++ b/213/CH13/EX13.2/13_2.sce
@@ -0,0 +1,27 @@
+//To design the gears

+clc

+//Given:

+x=600, pc=25 //mm

+N1=360, N2=120 //rpm

+//Solution:

+//Calculating the pitch circle diameters of each gear

+//Speed ratio, N1/N2 = d2/d1, or N1*d1-N2*d2 = 0                                .....(i)

+//Centre distance between the shafts, x = 1/2*(d1+d2), or d1+d2 = 600*2         .....(ii)

+A=[N1 -N2; 1 1]

+B=[0; 600*2]

+V=A \ B

+d1=V(1) //mm

+d2=V(2) //mm

+//Calculating the number of teeth on the first gear

+T1=round(%pi*d1/pc)

+//Calculating the number of teeth on the second gear

+T2=int(%pi*d2/pc+1)

+//Calculating the pitch circle diameter of the first gear

+d1dash=T1*pc/%pi //mm

+//Calculating the pitch circle diameter of the second gear

+d2dash=T2*pc/%pi //mm

+//Calculating the exact distance between the two shafts

+xdash=(d1dash+d2dash)/2 //mm

+//Results:

+printf("\n\n The number of teeth on the first and second gear must be %d and %d and their pitch circle diameters must be %.2f mm and %.1f mm respectively.\n\n",T1,T2,d1dash,d2dash)

+printf(" The exact distance between the two shafts must be %.2f mm.\n\n",xdash)
\ No newline at end of file
diff --git a/213/CH13/EX13.20/13_20.sce b/213/CH13/EX13.20/13_20.sce
new file mode 100755
index 000000000..c9550e416
--- /dev/null
+++ b/213/CH13/EX13.20/13_20.sce
@@ -0,0 +1,22 @@
+//To find teeth and torque

+clc

+//Given:

+Ts=100 //Torque on the sun wheel, N-m

+r=5 //Ratio of speeds of gear S to C, NS/NC

+//Refer Fig. 13.27 and Table 13.22

+//Number of teeth on different wheels:

+//Calculating the values of x and y

+y=1

+x=5-y

+//Calculating the number of teeth on wheel E

+TS=16

+TE=4*TS

+//Calculating the number of teeth on wheel P

+TP=(TE-TS)/2

+//Torque necessary to keep the internal gear stationary:

+Tc=Ts*r //Torque on CN-m

+//Caluclating the torque necessary to keep the internal gear stationary

+Ti=Tc-Ts //Torque necessary to keep the internal gear stationary, N-m

+//Results:

+printf("\n\n Number of teeth on different wheels, TE = %d.\n\n",TE)

+printf(" Torque necessary to keep the internal gear stationary = %d N-m.\n\n",Ti)
\ No newline at end of file
diff --git a/213/CH13/EX13.21/13_21.sce b/213/CH13/EX13.21/13_21.sce
new file mode 100755
index 000000000..948934810
--- /dev/null
+++ b/213/CH13/EX13.21/13_21.sce
@@ -0,0 +1,31 @@
+//To find speed, direction and torque

+clc

+//Given:

+TA=14, TC=100

+r=98/41 //TE/TD

+PA=1.85*1000 //W

+NA=1200 //rpm

+//Solution:

+//Refer Fig. 13.28 and Table 13.23

+//Calculating the number of teeth on wheel B

+TB=(TC-TA)/2

+//Calculating the values of x and y

+//From the fourth row of the table, -y+x*(TA/TC) = 0, or x*(TA/TC)-y = 0    .....(i)

+//Also, -x-y = 1200, or x+y = -1200                                         .....(ii)

+A=[TA/TC -1; 1 1]

+B=[0; -1200]

+V=A \ B

+x=V(1)

+y=V(2)

+//Calculating the speed of gear E

+NE=round(-y+x*(TA/TB)*(1/r)) //rpm

+//Fixing torque required at C:

+//Calculating the torque on A

+Ta=PA*60/(2*%pi*NA) //Torque on A, N-m

+//Calculating the torque on E

+Te=PA*60/(2*%pi*NE) //Torque on E

+//Calculating the fixing torque required at C

+Tc=Te-Ta //Fixing torque at C, N-m

+//Results:

+printf("\n\n Speed and direction of rotation of gear E, NE = %d rpm, anticlockwise.\n\n",NE)

+printf(" Fixing torque required at C = %.1f N-m.\n\n",Tc)
\ No newline at end of file
diff --git a/213/CH13/EX13.22/13_22.sce b/213/CH13/EX13.22/13_22.sce
new file mode 100755
index 000000000..5c3334122
--- /dev/null
+++ b/213/CH13/EX13.22/13_22.sce
@@ -0,0 +1,30 @@
+//To find holding torque

+clc

+//Given:

+TB=15, TA=60, TC=20

+omegaY=740, omegaA=omegaY //rad/s

+P=130*1000 //W

+//Solution:

+//Refer Fig. 13.29 and Table 13.24

+//Calculating the number of teeth on wheel D

+TD=TA-(TC+TB)

+//Calculating the values of x and y

+//From the fourth row of the table, y-x*(TD/TC)*(TB/TA) = 740            .....(i)

+//Also, x+y = 0, or y+x = 0                                              .....(ii)

+A=[1 -(TD/TC)*(TB/TA); 1 1]

+B=[740; 0]

+V=A \ B

+x=V(2)

+y=V(1)

+//Calculating the speed of shaft X

+omegaX=y //rad/s

+//Holding torque on wheel D:

+//Calculating the torque on A

+Ta=P/omegaA //Torque on A, N-m

+//Calculating the torque on X

+Tx=P/omegaX //Torque on X, N-m

+//Calculating the holding torque on wheel D

+Td=Tx-Ta //Holding torque on wheel D, N-m

+//Results:

+printf("\n\n Speed of shaft X, omegaX = %.1f rad/s.\n\n",omegaX)

+printf(" Holding torque on wheel D = %.1f N-m.\n\n",Td)
\ No newline at end of file
diff --git a/213/CH13/EX13.23/13_23.sce b/213/CH13/EX13.23/13_23.sce
new file mode 100755
index 000000000..8979893e1
--- /dev/null
+++ b/213/CH13/EX13.23/13_23.sce
@@ -0,0 +1,41 @@
+//To find speed, direction and torque

+clc

+//Given:

+TP=144, TQ=120, TR=120, TX=36, TY=24, TZ=30

+NI=1500 //rpm

+P=7.5*1000 //W

+eta=0.8

+//Solution:

+//Refer Fig. 13.30 and Table 13.25

+//Calculating the values of x and y

+//From the fourth row of the table, x+y = -1500        .....(i)

+//Also, y-x*(TZ/TR) = 0, or -x*(TZ/TR)+y = 0           .....(ii)

+A=[1 1; -TZ/TR 1]

+B=[-1500; 0]

+V=A \ B

+x=V(1)

+y=V(2)

+//Calculating the values of x1 and y1

+//We have, y1-x1*(TY/TQ) = y                           .....(iii)

+//Also, x1+y1 = x+y, or y1+x1 = x+y                    .....(iv)

+A=[1 -TY/TQ; 1 1]

+B=[y; x+y]

+V=A \ B

+x1=V(2)

+y1=V(1)

+//Speed and direction of the driven shaft O and the wheel P:

+//Calculating the speed of shaft O

+NO=y1 //rpm

+//Calculating the speed of wheel P

+NP=y1+x1*(TY/TQ)*(TX/TP) //rpm

+//Torque tending to rotate the fixed wheel R:

+//Calculating the torque on shaft I

+T1=P*60/(2*%pi*NI) //N-m

+//Calculating the torque on shaft O

+T2=eta*P*60/(2*%pi*(-NO)) //N-m

+//Calculating the torque tending to rotate the fixed wheel R

+T=T2-T1 //Torque tending to rotate the fixed wheel R, N-m

+//Results:

+printf("\n\n Speed of the driven shaft O, NO = %d rpm, clockwise.\n\n",-NO)

+printf(" Speed of the wheel P, NP = %d rpm, clockwise.\n\n",-NP)

+printf(" Torque tending to rotate the fixed wheel R = %.2f N-m.\n\n",T)
\ No newline at end of file
diff --git a/213/CH13/EX13.24/13_24.sce b/213/CH13/EX13.24/13_24.sce
new file mode 100755
index 000000000..3daef9bd1
--- /dev/null
+++ b/213/CH13/EX13.24/13_24.sce
@@ -0,0 +1,44 @@
+//To find torque and forces

+clc

+//Given:

+TA=34, TB=120, TC=150, TD=38, TE=50

+PX=7.5*1000 //W

+NX=500 //rpm

+m=3.5 //mm

+//Solution:

+//Refer Fig. 13.31 and Table 13.27

+//Output torque of shaft Y:

+//Calculating the values of x and y

+//From the fourth row of the table, x+y = 500, or y+x = 500        .....(i)

+//Also, y-x*(TA/TC) = 0                                            .....(ii)

+A=[1 1; 1 -TA/TC]

+B=[500; 0]

+V=A \ B

+y=V(1) //rpm

+x=V(2) //rpm

+//Calculating the speed of output shaft Y

+NY=y-x*(TA/TB)*(TD/TE) //rpm

+//Calculating the speed of wheel E

+NE=NY //rpm

+//Calculating the input power assuming 100 per cent efficiency

+PY=PX //W

+//Calculating the output torque of shaft Y

+Ty=PY*60/(2*%pi*NY*1000) //Output torque on shaft Y, kN-m

+//Tangential force between wheels D and E:

+//Calculating the pitch circle radius of wheel E

+rE=m*TE/(2*1000) //m

+//Calculating the tangential force between wheels D and E

+FtDE=Ty/rE //Tangential force between wheels D and E, kN

+//Tangential force between wheels B and C:

+//Calculating the input torque on shaft X

+Tx=PX*60/(2*%pi*NX) //Input torque on shaft X, N-m

+//Calculating the fixing torque on the fixed wheel C

+Tf=Ty-Tx/1000 //Fixing torque on the fixed wheel C, kN-m

+//Calculating the pitch circle radius of wheel C

+rC=m*TC/(2*1000) //m

+//Calculating the tangential forces between wheels B and C

+FtBC=Tf/rC //kN

+//Results:

+printf("\n\n Output torque of shaft Y = %.3f kN-m.\n\n",Ty)

+printf(" Tangential force between wheels D and E = %.1f kN.\n\n",FtDE)

+printf(" Tangential force between wheels B and C = %d kN.\n\n",FtBC)
\ No newline at end of file
diff --git a/213/CH13/EX13.3/13_3.sce b/213/CH13/EX13.3/13_3.sce
new file mode 100755
index 000000000..73ddee044
--- /dev/null
+++ b/213/CH13/EX13.3/13_3.sce
@@ -0,0 +1,34 @@
+//To find the number of teeth

+clc

+//Given:

+rAD=12 //Speed ratio, NA/ND

+mA=3.125, mB=mA, mC=2.5, mD=mC, x=200 //mm

+//Solution:

+//Calculating the speed ratio between the gears A and B, and C and D

+rAB=sqrt(rAD) //Speed ratio between the gears A and B

+rCD=sqrt(rAB) //Speed ratio between the gears C and D

+//Calculating the ratio of teeth on gear B to gear A

+rtBA=rAB //Ratio of teeth on gear B to gear A

+//Calculating the ratio of teeth on gear D to gear C

+rtDC=rCD //Ratio of teeth on gear D to gear C

+//Calculating the number of teeth on the gears A and B

+//Distance between the shafts, x = mA*TA/2+mB*TB/2, or (mA/2)*TA+(mB/2)*TB = x        .....(i)

+//Ratio of teeth on gear B to gear A, TB/TA = sqrt(12), or sqrt(12)*TA-TB = 0         .....(ii)

+A=[mA/2 mB/2; sqrt(12) -1]

+B=[x; 0]

+V=A \ B

+TA=int(V(1))

+TB=round(V(2))

+//Calculating the number of teeth on the gears C and D

+//Distance between the shafts, x = mC*TC/2+mD*TD/2, or (mC/2)*TC+(mD/2)*TD = x        .....(iii)

+//Ratio of teeth on gear D to gear C, TD/TC = sqrt(12), or sqrt(12)*TC-TD = 0         .....(iv)

+A=[mC/2 mD/2; sqrt(12) -1]

+B=[x; 0]

+V=A \ B

+TC=round(V(1))

+TD=int(V(2))

+//Results:

+printf("\n\n Number of teeth on gear A, TA = %d.\n\n",TA)

+printf(" Number of teeth on gear B, TB = %d.\n\n",TB)

+printf(" Number of teeth on gear C, TC = %d.\n\n",TC)

+printf(" Number of teeth on gear D, TD = %d.\n\n",TD)
\ No newline at end of file
diff --git a/213/CH13/EX13.4/13_4.sce b/213/CH13/EX13.4/13_4.sce
new file mode 100755
index 000000000..0042351ec
--- /dev/null
+++ b/213/CH13/EX13.4/13_4.sce
@@ -0,0 +1,17 @@
+//To find speed of gear B

+clc

+//Given:

+TA=36, TB=45

+NC=150 //rpm, anticlockwise

+//Solution:

+//Refer Fig. 13.7

+//Algebraic method:

+//Calculating the speed of gear B when gear A is fixed

+NA=0, NC=150 //rpm

+NB1=(-TA/TB)*(NA-NC)+NC //rpm

+//Calculating the speed of gear B when gear A makes 300 rpm clockwise

+NA=-300 //rpm

+NB2=(-TA/TB)*(NA-NC)+NC //rpm

+//Results:

+printf("\n\n Speed of gear B when gear A is fixed, NB = %d rpm.\n\n",NB1)

+printf(" Speed of gear B when gear A makes 300 rpm clockwise, NB = %d rpm.\n\n",NB2)
\ No newline at end of file
diff --git a/213/CH13/EX13.5/13_5.sce b/213/CH13/EX13.5/13_5.sce
new file mode 100755
index 000000000..fd14423a4
--- /dev/null
+++ b/213/CH13/EX13.5/13_5.sce
@@ -0,0 +1,15 @@
+//To find speed of gear C

+clc

+//Given:

+TB=75, TC=30, TD=90

+NA=100 //rpm, clockwise

+//Solution:

+//Refer Table 13.3

+//Calculating the number of teeth on gear E

+TE=TC+TD-TB

+//Calculating the speed of gear C

+y=-100

+x=y*(TB/TE)

+NC=y-x*(TD/TC) //rpm

+//Results:

+printf("\n\n Speed of gear C, NC = %d rpm, anticlockwise.\n\n",NC)
\ No newline at end of file
diff --git a/213/CH13/EX13.6/13_6.sce b/213/CH13/EX13.6/13_6.sce
new file mode 100755
index 000000000..761ebd50c
--- /dev/null
+++ b/213/CH13/EX13.6/13_6.sce
@@ -0,0 +1,19 @@
+//To find speed of gears B and C

+clc

+//Given:

+TA=72, TC=32

+NEF=18 //Speed of arm EF, rpm

+//Solution:

+//Refer Table 13.5

+//Speed of gear C:

+y=18 //rpm

+x=y*(TA/TC)

+NC=x+y //Speed of gear C, rpm

+//Speed of gear B:

+//Calculating the number of teeth on gear B

+TB=(TA-TC)/2

+//Calculating the speed of gear B

+NB=y-x*(TC/TB) //Speed of gear B, rpm

+//Solution:

+printf("\n\n Speed of gear C = %.1f rpm.\n\n",NC)

+printf(" Speed of gear B = %.1f rpm in the opposite direction of arm.\n\n",-NB)
\ No newline at end of file
diff --git a/213/CH13/EX13.7/13_7.sce b/213/CH13/EX13.7/13_7.sce
new file mode 100755
index 000000000..1a8a9f6fd
--- /dev/null
+++ b/213/CH13/EX13.7/13_7.sce
@@ -0,0 +1,37 @@
+//To find revolutions of arm

+clc

+//Given:

+TA=40, TD=90

+//Solution:

+//Calculating the number of teeth on gears B and C

+//From geometry of the Fig. 13.11, dA+2*dB=dD.

+//Since the number of teeth are proportional to their pitch circle diameters,

+TB=(TD-TA)/2

+TC=TB

+//Refer Table 13.6

+//Speed of arm when A makes 1 revolution clockwise and D makes half revolution anticlockwise:

+//Calculating the values of x and y

+//From the fourth row of the table, -x-y = -1, or x+y = 1                            .....(i)

+//The gear D makes half revolution anticlockwise, i.e., x*(TA/TD)-y = 1/2            .....(ii)

+A=[1 1; TA/TD -1]

+B=[1; 1/2]

+V=A \ B

+x=V(1)

+y=V(2)

+//Calculating the speed of arm

+varm=-y //Speed of arm, revolutions

+//Results:

+printf("\n\n Speed of arm when A makes 1 revolution clockwise and D makes half revolution anticlockwise = %.2f revolution anticlockwise.\n\n",varm)

+//Speed of arm when A makes 1 revolution clockwise and D is stationary:

+//Calculating the values of x and y

+//From the fourth row of the table, -x-y = -1, or x+y = 1                            .....(iii)

+//The gear D is stationary, i.e., x*(TA/TD)-y = 0                                    .....(iv)

+A=[1 1; TA/TD -1]

+B=[1; 0]

+V=A \ B

+x=V(1)

+y=V(2)

+//Calculating the speed of arm

+varm=-y //Speed of arm, revolutions

+//Results:

+printf(" Speed of arm when A makes 1 revolution clockwise and D is stationary = %.3f revolution clockwise.\n\n",-varm)
\ No newline at end of file
diff --git a/213/CH13/EX13.8/13_8.sce b/213/CH13/EX13.8/13_8.sce
new file mode 100755
index 000000000..2deb4b7cb
--- /dev/null
+++ b/213/CH13/EX13.8/13_8.sce
@@ -0,0 +1,28 @@
+//To find teeth and speed

+clc

+//Given:

+TC=28, TD=26, TE=18, TF=TE

+//Solution:

+//The sketch is as in Fig. 13.12

+//Number of teeth on  wheels A and B:

+//From geometry, dA = dC+2*dE, and dB = dD+2*dF

+//Since the number of teeth are proportional to their pitch circle diameters,

+TA=TC+2*TE

+TB=TD+2*TF

+//Speed of wheel B when arm G makes 100 rpm clockwise and wheel A is fixed:

+//Since the arm G makes 100 rpm clockwise, therefore from the fourth row of Table 13.7,

+y=-100

+x=-y

+//Calculating the speed of wheel B

+NB1=y+x*(TA/TC)*(TD/TB) //Speed of wheel B when arm G makes 100 rpm clockwise and wheel A is fixed, rpm

+//Speed of wheel B when arm G makes 100 rpm clockwise and wheel A makes 10 rpm counter clockwise:

+//Since the arm G makes 100 rpm clockwise, therefore from the fourth row of Table 13.7,

+y=-100

+x=10-y

+//Calculating the speed of wheel B

+NB2=y+x*(TA/TC)*(TD/TB) //Speed of wheel B when arm G makes 100 rpm clockwise and wheel A makes 10 rpm counter clockwise, rpm

+//Solution:

+printf("\n\n Number of teeth on  wheel A, TA = %d.\n\n",TA)

+printf(" Number of teeth on  wheel B, TB = %d.\n\n",TB)

+printf(" Speed of wheel B when arm G makes 100 rpm clockwise and wheel A is fixed = %.1f rpm, clockwise.\n\n",-NB1)

+printf(" Speed of wheel B when arm G makes 100 rpm clockwise and wheel A makes 10 rpm counter clockwise = %.1f rpm, counter clockwise.\n\n",NB2)
\ No newline at end of file
diff --git a/213/CH13/EX13.9/13_9.sce b/213/CH13/EX13.9/13_9.sce
new file mode 100755
index 000000000..5b476cfac
--- /dev/null
+++ b/213/CH13/EX13.9/13_9.sce
@@ -0,0 +1,19 @@
+//To find number of teeth

+clc

+//Given:

+dD=224, m=4 //mm

+//Solution:

+//Refer Table 13.8

+//Calculating the values of x and y

+y=+1

+x=+5-y

+//Calculating the number of teeth on gear D

+TD=dD/m

+//Calculating the number of teeth on gear B

+TB=y/x*TD

+//Calculating the number of teeth on gear C

+TC=(TD-TB)/2

+//Results:

+printf("\n\n Number of teeth on gear D, TD = %d.\n\n",TD)

+printf(" Number of teeth on gear B, TB = %d.\n\n",TB)

+printf(" Number of teeth on gear C, TC = %d.\n\n",TC)
\ No newline at end of file