equation for projectile motion

hello im currenrty trying to find the displacement of a marbel falling of a ramp at 0.5 ft/s (Vi). the ramp varies anywhere from 0 to 30 degrees. it alsois 4 ft from i know that to use the kinematic equations i have to relate everything to time however i belive that my equation may be wrong because when i double check my work that data does not reflect that of the graph created in matlab. Below is a copy of my code...

clc

clear all

velocity=0.5;

figure;

hold on;

function d = projMotion(velocity,height,angle)

Vyi=velocity*sind(angle);

g=9.81;

tmax=(2*Vyi/g+sqrt((2*Vyi/g)^2+8*height/g))/2;

t=0:.001:tmax;

d=height+Vyi*t-.5*g*t.^2;

plot(t,d)

end

for height=4

for angle=0:1:30

d=projMotion(velocity,height,angle);

end

end

Answer 1

[Stephan]

This might be helpful: https://de.mathworks.com/matlabcentral/answers/431384-write-a-script-which-will-calculate-the-trajectory-of-a-ball-thrown-at-an-initial-speed-vo-ask-the