initial commit / add all books

19 files changed, 284 insertions, 0 deletions

diff --git a/3137/CH9/EX9.1/Ex9_1.sce b/3137/CH9/EX9.1/Ex9_1.sce
new file mode 100755
index 000000000..74f3aa18c
--- /dev/null
+++ b/3137/CH9/EX9.1/Ex9_1.sce
@@ -0,0 +1,15 @@
+//Calculations

+//Simplifying  equation (3) after substituting value of Nb in it we get

+//m_u^2+m_u*2*tand(50)-1=0

+//Solution of the equation

+a=1

+b=2*tand(50)

+c=-1

+g=sqrt(b^2-(4*a*c))

+//solution

+x1=(-b+g)/(2*a)

+x2=(-b-g)/(2*a)

+//As x2 does not make any physical sense x1 is the answer

+//Result

+clc

+printf('The value of mu is %f',x1)

diff --git a/3137/CH9/EX9.10/Ex9_10.sce b/3137/CH9/EX9.10/Ex9_10.sce
new file mode 100755
index 000000000..a6e58662f
--- /dev/null
+++ b/3137/CH9/EX9.10/Ex9_10.sce
@@ -0,0 +1,17 @@
+//Initilization of variables

+mu=0.2 //coefficient of friction

+F1=150 //lb

+F2=100 //lb

+theta=60 //degrees

+//Calculations

+N1=F1*cosd(theta) //lb

+T=(mu*N1+(F1*cosd(theta/2))) //lb considering positive

+//Equilibrium for 100lb

+//Eliminating N2 from both equations

+//Taking derivative we get

+theta2=atand(mu) //degrees

+//Hence P becomes

+P=(F2*mu+T)/(cosd(theta2)+(mu*sind(theta2))) //lb

+//Result

+clc

+printf('The minimum value of P is %flb',P)

diff --git a/3137/CH9/EX9.11/Ex9_11.sce b/3137/CH9/EX9.11/Ex9_11.sce
new file mode 100755
index 000000000..c1a7a8927
--- /dev/null
+++ b/3137/CH9/EX9.11/Ex9_11.sce
@@ -0,0 +1,14 @@
+//Initilization of variables

+F=180 //N

+m=100 //kg

+g=9.81 //m/s^2

+mu=0.25 //coeffiecient of friction

+//Calculations

+//Assuming F2 is maximum

+N2=F*2/(1+mu) //N

+F2=mu*N2 //N

+N1=m*g-F2 //N

+F1=F-F2 //N

+//Result

+clc

+printf('The vaules are N2=%fN,F2=%fN,N1=%fN and F1=%fN',N2,F2,N1,F1)

diff --git a/3137/CH9/EX9.12/Ex9_12.sce b/3137/CH9/EX9.12/Ex9_12.sce
new file mode 100644
index 000000000..69f3614ea
--- /dev/null
+++ b/3137/CH9/EX9.12/Ex9_12.sce
@@ -0,0 +1,9 @@
+//Initilization of variables
+N=4/3 //Normal reaction after solving without the mg term in it
+u_N=1/2 //Frictional force without the mg term in it
+//Calculations
+u=u_N/N //Coefficient of friction
+//Result
+clc
+printf("The frictional co-efficient is %f",u)
+//The answer in the textbook and the code differs due to multiplication of fractions
diff --git a/3137/CH9/EX9.13/Ex9_13.sce b/3137/CH9/EX9.13/Ex9_13.sce
new file mode 100755
index 000000000..cb05722c6
--- /dev/null
+++ b/3137/CH9/EX9.13/Ex9_13.sce
@@ -0,0 +1,22 @@
+//Initilization of variables

+mu_ca=0.3 //ceofficient of friction between copper block A and aluminium block B

+mu_af=0.2 //coefficient of friction between aluminium block B and Floor

+ma=3 //kg

+mb=2 //kg

+g=9.81 //m/s^2

+//Calculations

+//For A

+//Taking sum of forces along X and Y direction

+Na=ma*g //N

+P=mu_ca*Na //N

+//For B

+//Taking sum of forces along X and Y direction

+Nb=Na+mb*g //N

+Fb=mu_ca*Na //N

+//Now largest value of friction before slip is 

+Fprimeb=mu_af*Nb //N

+//Now as Fb<F'b hence initial assumption is incorrect and P=Fb

+P=Fb //N

+//Result

+clc

+printf('The value of force that will cause motion is %fN',P)

diff --git a/3137/CH9/EX9.15/Ex9_15.sce b/3137/CH9/EX9.15/Ex9_15.sce
new file mode 100755
index 000000000..f8f46f5d2
--- /dev/null
+++ b/3137/CH9/EX9.15/Ex9_15.sce
@@ -0,0 +1,16 @@
+//Initilization of variables

+d_m=2 //in   mean diameter of the screw

+p=1/4 //in

+mu=0.15 //coefficient of friction

+l=2 //ft

+L=4000 //lb

+//Calculations

+phi=atand(mu) //degrees

+beta=atand(p/(%pi*l)) //degrees

+//Force to raise the load

+P=(L*tand(phi+beta))/(d_m*12) //lb

+//Force to lower the load

+P2=(L*tand(phi-beta))/(d_m*12) //lb

+//Result

+clc

+printf('The force to raise the load is %flb and to lower is %flb',P,P2 )

diff --git a/3137/CH9/EX9.16/Ex9_16.sce b/3137/CH9/EX9.16/Ex9_16.sce
new file mode 100755
index 000000000..eddef10c8
--- /dev/null
+++ b/3137/CH9/EX9.16/Ex9_16.sce
@@ -0,0 +1,14 @@
+//Initilization of variables

+r_m=2.338 //in

+d_m=3.25 //in

+mu=0.06 //coefficient of friction

+P=1500 //lb

+p=1/4 //pitch

+//Calculation

+phi=atand(mu) //degrees

+beta=atand(p/(2*%pi*r_m)) //degrees

+M=P*r_m*tand(phi+beta)+mu*P*(d_m/2) //lb.in

+//Result

+clc

+printf('The moment required is %flb-in',M)

+//Decimal accuracy causes discrepancy in answers

diff --git a/3137/CH9/EX9.17/Ex9_17.sce b/3137/CH9/EX9.17/Ex9_17.sce
new file mode 100755
index 000000000..177b53093
--- /dev/null
+++ b/3137/CH9/EX9.17/Ex9_17.sce
@@ -0,0 +1,11 @@
+//Initilization of variables

+d=750 //mm diameter

+alpha=%pi //wrap angle    radians

+mu=0.25 //coefficient of friction

+T_t=200 //N tension on the tight side

+//Calculation

+T2=T_t/(exp(mu*alpha)) //N

+//Result

+clc

+printf('The tension of the slack side is %fN',T2)

+

diff --git a/3137/CH9/EX9.18/Ex9_18.sce b/3137/CH9/EX9.18/Ex9_18.sce
new file mode 100755
index 000000000..73259cf66
--- /dev/null
+++ b/3137/CH9/EX9.18/Ex9_18.sce
@@ -0,0 +1,25 @@
+//Initilization of variables

+d=635 //mm diameter of the drum

+P=178 //N

+mu=1/3 //coefficient of friction

+l1=100 //mm 

+l2=660 //mm

+theta1=60 //degrees

+GD=d/2 //mm

+//Calculations

+//Taking moment about point C

+Tb=(P*(l1+l2))/(l1*sind(theta1)) //N

+CD=((d/2)-(l1*cosd(theta1/2)))/sind(theta1/2) //mm

+//from fig 9-22(b) 

+theta=asind(GD/CD) //degrees

+//from fig9-22(c)

+w_d=180+30+theta //degrees

+w=(w_d)*(%pi/180) //radians

+//As Tc is greater than Tb

+Tc=Tb*(exp(mu*w)) //N

+M=(Tc-Tb)*GD //N.mm

+an=M/1000 //N.m

+//Result

+clc

+printf('The braking moment required is %fN-m',an)

+//Note the unit of the final enswer carefully

diff --git a/3137/CH9/EX9.19/Ex9_19.sce b/3137/CH9/EX9.19/Ex9_19.sce
new file mode 100755
index 000000000..d79e99a17
--- /dev/null
+++ b/3137/CH9/EX9.19/Ex9_19.sce
@@ -0,0 +1,8 @@
+//Initilization of variables

+L=1000 //lb

+P=10 //lb

+//Calculations

+mu=log(L/P)/(4*2*%pi) 

+//Result

+clc

+printf('The coefficient of friction is %f',mu)

diff --git a/3137/CH9/EX9.20/Ex9_20.sce b/3137/CH9/EX9.20/Ex9_20.sce
new file mode 100755
index 000000000..a962a5590
--- /dev/null
+++ b/3137/CH9/EX9.20/Ex9_20.sce
@@ -0,0 +1,9 @@
+//Initilization of variables

+m=900 //kg

+mu=0.2 //coefficient of friction

+g=9.8 //m/s^2

+//Calculations

+T2=m*g/(exp(2*2*%pi*mu)) //N

+//Result

+clc

+printf('The force needed to hold the mass is %fN',T2)

diff --git a/3137/CH9/EX9.21/Ex9_21.sce b/3137/CH9/EX9.21/Ex9_21.sce
new file mode 100755
index 000000000..973fddcd0
--- /dev/null
+++ b/3137/CH9/EX9.21/Ex9_21.sce
@@ -0,0 +1,10 @@
+//Initilization of variables

+d=760 //mm

+W=500 //N

+a=0.305 //mm coefficient of rolling resisatnce

+r=d/2 //mm

+//Calculations

+P=(W*a)/r //N

+//Result

+clc

+printf('The force necessary is P=%fN',P)

diff --git a/3137/CH9/EX9.3/Ex9_3.sce b/3137/CH9/EX9.3/Ex9_3.sce
new file mode 100755
index 000000000..55e9ec48e
--- /dev/null
+++ b/3137/CH9/EX9.3/Ex9_3.sce
@@ -0,0 +1,22 @@
+//Initilization of variables

+m=70 //kg

+g=9.81 //m/s^2

+theta=20 //degrees

+//Calculations

+//Solving by martix method

+//Taking sum along vertical and horizontal direction and equating them to zero

+A=[sind(theta) 1 0;-cosd(theta) 0 1;0 -1/4 1]

+//RHS matrix

+R=[m*g;0;0]

+ans1=inv(A)*R //force vector N

+//Calculation part 2

+//Similar solution by matrix method

+//Taking moment about point O and summing forces in horizontal and vertical direction and equating all to zero

+B=[4*cosd(theta) 0 0;-cosd(theta) 1 0;sind(theta) 0 1]

+//RHS matrix

+J=[m*g*1.5;0;m*g]

+ans2=inv(B)*J //force Vector N

+//Result

+clc

+printf('The value of P in first case is %iN and that in second case is %iN',ans1(1),ans2(1))

+ 

diff --git a/3137/CH9/EX9.4/Ex9_4.sce b/3137/CH9/EX9.4/Ex9_4.sce
new file mode 100644
index 000000000..1beaa1e0b
--- /dev/null
+++ b/3137/CH9/EX9.4/Ex9_4.sce
@@ -0,0 +1,14 @@
+//Initilization of variables

+W=200 //lb

+Fapp=300 //lb

+mu=0.3 //coefficient of friction

+theta=30 //degrees

+//Calculations

+//Summing forces in the plane parallel to the slope

+F=-(W*sind(theta)-Fapp*cosd(theta)) //lb

+N1=(W*cosd(theta)+Fapp*sind(theta)) //lb

+//Max value obtained

+Fprime= mu*N1

+//Result

+clc

+printf('The value of F and N1 are %flb and %flb respectively and the maximum value obtained is %flb',F,N1,Fprime)

diff --git a/3137/CH9/EX9.5/Ex9_5.sce b/3137/CH9/EX9.5/Ex9_5.sce
new file mode 100755
index 000000000..6baaf9041
--- /dev/null
+++ b/3137/CH9/EX9.5/Ex9_5.sce
@@ -0,0 +1,15 @@
+//Initilization of variables

+mu1=0.2 //coefficient of friction between wedges and A

+mu2=1/4 //coefficient of friction between wedges 

+F=20 //tonnes

+//Calculations

+//Using the matrix method to solve

+//Summing forces in vertical and horizontal direction

+A=[1,-(mu1*10+1)/(sqrt(101));0, (10-mu1*1)/sqrt(101)] //force matrix

+B=[mu2*F*1000;F*1000] //lb

+//Solving both matrices

+R=inv(A)*B //lb

+//Result

+clc

+printf('The forces N2 and P are %ilb and %ilb respectively',R(2),R(1))

+//Decimal accuracy causes discrepancy in answers

diff --git a/3137/CH9/EX9.6/Ex9_6.sce b/3137/CH9/EX9.6/Ex9_6.sce
new file mode 100755
index 000000000..e605012ae
--- /dev/null
+++ b/3137/CH9/EX9.6/Ex9_6.sce
@@ -0,0 +1,22 @@
+//Initilization of variables

+theta=45 //degrees

+mu1=1/4 //coefficient of friction between A and B

+mu2=1/3 //coefficient of friction between A and Floor

+ma=14 //kg

+mb=9 //kg

+g=9.81 //m/s^2

+//Calculations

+//Summing forces in vertical direction

+Nb=mb*g //N

+//Also

+Fprimeb=mu1*Nb //N

+//Summing forces in direction

+T=Fprimeb //N

+//Considering the fig(c)

+//Summing forces in the horizontal direction and vertical direction and solving by matrix method 

+A=[-cosd(theta) mu2;sind(theta) 1] //N

+B=[-Fprimeb;(mb*g+ma*g)] //N

+R=inv(A)*B //N

+//Result

+clc

+printf('The value of P and Na are %fN and %fN respectively',R(1),R(2))

diff --git a/3137/CH9/EX9.7/Ex9_7.sce b/3137/CH9/EX9.7/Ex9_7.sce
new file mode 100755
index 000000000..10428bcb2
--- /dev/null
+++ b/3137/CH9/EX9.7/Ex9_7.sce
@@ -0,0 +1,14 @@
+//Initilization of variables

+m1=40 //kg

+m2=13.5 //kg

+mu=1/3 //coefficient of friction

+g=9.81 //m/s^2

+//Calculations

+//Solving by substitution

+//After simplification we get

+x=mu*m2*g

+y=mu*(m1*g+m2*g)

+theta=atand((x+y)/(m1*g)) //degrees

+//Result

+clc

+printf('The value of the angle is %f degrees',theta) 

diff --git a/3137/CH9/EX9.8/Ex9_8.sce b/3137/CH9/EX9.8/Ex9_8.sce
new file mode 100755
index 000000000..5c8f7f393
--- /dev/null
+++ b/3137/CH9/EX9.8/Ex9_8.sce
@@ -0,0 +1,12 @@
+//Initilization of variables

+W=350 //lb

+theta=30 //degrees

+phi=15 //degrees

+//Calculations

+//Solving by the matrix method

+A=[cosd(theta) sind(phi);-sind(theta) cosd(phi)]

+B=[W*sind(theta);W*cosd(theta)]

+an=inv(A)*B //lb

+//Result

+clc

+printf('The value of P and R are %flb and %flb respectively',an(1),an(2))

diff --git a/3137/CH9/EX9.9/Ex9_9.sce b/3137/CH9/EX9.9/Ex9_9.sce
new file mode 100755
index 000000000..12b59de2f
--- /dev/null
+++ b/3137/CH9/EX9.9/Ex9_9.sce
@@ -0,0 +1,15 @@
+//Initilization of variables

+theta=45 //degrees

+m1=45 //kg

+m2=135 //kg

+g=9.81 //m/s^2

+mu=0.25 //coefficient of riction

+//Calculations

+N2=m2*g //N

+T=mu*N2 //N

+N1=m1*g*cosd(theta) //N

+Fprime1=N1*mu //N

+P=T+Fprime1-(m1*g*sind(theta)) //N

+//Result

+clc

+printf('The values are N2=%fN,T=%fN,N1=%fN,Fprime1=%fN and P=%fN',N2,T,N1,Fprime1,P)