Knowledge on Physics

Good morning everyone. I’m new to gdevelop. I absolutely love it though. I’d like to create a small game. Basically it’s a ball in a box bouncing around and a triangle is the character. The triangle moves around dodging the ball. If the ball touches the triangle it is deleted. I can’t seem to get the ball bouncing constant. It’s either bouncing extremely fast or bouncing slow then stop. But always roll to lower right. Why? How can I get more knowledge on events? Variables? X axis Y axis? I want to be better.

Nevermind. I found it in an example.