How do I add speed?

Please tell me how to add speed to an object. Not to install, but to add. I have objects falling, and it is necessary that every 5 seconds, for example, the speed of their fall increases.

Here is some example

Add Bullet Behavior To Object

and in event sheet

Every 5 second add +5

Thank you, but what exactly did you write in the meaning?+5 or add +5 nothing works for me from this

That's it, I figured it out))) thank you very much