collar_potential_energy.m

function totalPE = collar_potential_energy(x_C,theta)
% Solves the potential energy of a collar on a rod given initial position and angle.
% USAGE: totalPE = collar_potential_energy(x_C,theta)

m = 0.5; % mass is 0.5 kg
g = -9.81; % acceleration due to gravity
k = 30; % spring constant

PE_g= m*x_C*g*sind(theta); % potential energy due to gravity 

DL = 0.5 - sqrt((0.5^2) - ((0.5-x_C).^2)); 
PE_s = 0.5*k.*((DL).^2); % potentual energy due to spring

totalPE = PE_g + PE_s;
end