How to make physics forces independent of frame rate?

I have very simple 2d platformer game and I couldnt achieve fixed velocity on spawn items on different fps. My project is based on blueprints. And my character spawn items from his inventory. Can someone help me please how can I made this? I am using delta time, on event tick i am dividing by 1, my delta time works perfect with character jump and other things, such as enemy movement.But I couldnt achieve fixed velocity on add impulse or add force when I spawn an item… Can anybody help me about it? If I use projectile movement my item direclty goes down without collision.