i need to find the displacement for the given values

1 view (last 30 days)
clear all
syms p E v a b d A I G m U
p = 10
E = 3*10^4
v = 0.29
a = 39
b = 2*a
d = 1
A = pi/4
I = (pi/64)*d^2
G = E/(2*(1+v))
m = 5/6
U = p^2*a^2/(2*E*I)+p^2*a/(2*m*G*A)+p^2*b/(2*E*A)+p^2*b/2*E*A+p^2*a^3/2*G*I+p^2*a/2*G*m*A
disp = diff(U,p);

Answers (1)

Torsten
Torsten on 2 Dec 2022
Edited: Torsten on 2 Dec 2022
syms p
E = 3*10^4;
v = 0.29;
a = 39;
b = 2*a;
d = 1;
A = pi/4;
I = (pi/64)*d^2;
G = E/(2*(1+v));
m = 5/6;
U = p^2*a^2/(2*E*I)+p^2*a/(2*m*G*A)+p^2*b/(2*E*A)+p^2*b/2*E*A+p^2*a^3/2*G*I+p^2*a/2*G*m*A;
dUdp = diff(U,p);
p0 = 10;
disp(double(subs(dUdp,p,p0)))
3.5993e+08
  3 Comments
Torsten
Torsten on 2 Dec 2022
Edited: Torsten on 2 Dec 2022
dUdp is a symbolic expression that depends on the symbolic variable p.
subs substitutes the value p0=10 for the symbolic variable p. The result is still symbolic.
double converts the symbolic value into a double value.
disp displays this value.
But is diff(U,p) really the displacement ? What is U ? What is p ?
sai nikhil teja
sai nikhil teja on 4 Dec 2022
U is the energy and du/dp is the displacement. p is the force that is causing the dispalacement. This is the castiligio theorm where differentiating the energy equation with the force gives us the vertical displacement.

Sign in to comment.

Categories

Find more on Symbolic Math Toolbox in Help Center and File Exchange

Products

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!