diff --git a/src/Makefile.am b/src/Makefile.am
index 8c71a01..027165d 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -9,4 +9,4 @@ pong_SOURCES = \
 	racket.c \
 	racket.h
 pong_CFLAGS = $(SDL_CFLAGS)
-pong_LDFLAGS = $(SDL_LIBS)
+pong_LDFLAGS = $(SDL_LIBS) -lm
diff --git a/src/ball.c b/src/ball.c
index da6d7d5..9ccde49 100644
--- a/src/ball.c
+++ b/src/ball.c
@@ -1,9 +1,13 @@
+#include <stdlib.h> // srand, rand
+#include <time.h> // time
+#include <math.h> // sin, cos, M_PI
 #include "ball.h"
 #include "racket.h"
 
 Ball*
 Ball_init(int screen_width, int screen_height)
 {
+  srand(time(NULL));
   Ball *b = malloc(sizeof(Ball));
   *(int *)&b->BALL_WIDTH = 20;
   *(int *)&b->BALL_HEIGHT = 20;
@@ -16,10 +20,12 @@ Ball_init(int screen_width, int screen_height)
 
 void
 Ball_reset(Ball *b, int direction) {
+  // 120 deg angle with norm horizontal vector
+  const int angle = rand() % 60 + 60;
   b->posX = b->SCREEN_WIDTH/2;
   b->posY = b->SCREEN_HEIGHT/2;
-  b->velX = direction * 7;
-  b->velY = 5;
+  b->velX = direction * b->BALL_VELOCITY * cos(angle * 2 * M_PI / 180);
+  b->velY = b->BALL_VELOCITY * sin(angle * 2 * M_PI / 180);
 }
 
 void