diff --git a/main_ball.cpp b/main_ball.cpp
index 75eda5f..93f6b8e 100644
--- a/main_ball.cpp
+++ b/main_ball.cpp
@@ -11,7 +11,7 @@ using namespace std;
 int main(int argc, char** argv) {
     int i;
     Point center(0,0,10);
-    Ball ball(center, 0, 1, 1);
+    Ball ball(center, 0, 0, 1, 1);
     for(i=0; i< 10000; i++) {
         ball.update_pos(0.001);
         cout << ball << "\n";